When a transaction is questioned by the cardholder and a dispute is issued, you’ll receive an email with all the details of the disputed transaction.

You will have a limited time to respond before the dispute expires and the funds are ultimately lost to you.

Response timeframe

The time you have to respond depends on the card issuer as outlined in the table below. We recommend that you act as quickly as possible.

Card issuer	Time to respond from the date you received the dispute
Mastercard	14 days
Visa	14 days
AMEX	7 days

IMPORTANT: Disputes must be actioned within the stated time period. This includes providing evidence and all supported documents. Failure to take action within the time limit will result in an automatically lost dispute. This outcome is final and cannot be undone. The decision is made by the schemes (Visa, Mastercard, etc.) and is outside of Mamo's control.

Within this timeframe, your options are:

Talking to the customer: Try to resolve the issue directly with your customer. If they agree to cancel or withdraw the dispute, they must contact their bank directly.
Accepting the dispute: You agree with the dispute and the deduction of the funds. In this case, you need to accept the dispute in the Mamo dashboard.
Challenging the dispute: You don’t agree with the dispute and want to defend the charge. In this case, you need to submit evidence via the Mamo dashboard.
Ignoring the dispute: If you take no action within the required time, the dispute expires and is automatically lost.

Dispute fees apply in all cases. A dispute processing fee of AED 110 is applied to every single dispute you receive and is non-refundable, regardless of the outcome of the dispute.

Accepting a dispute

You agree with the dispute that was issued by the customer and the deduction of the funds. In this case, you need to accept the dispute in the Mamo dashboard:

Go to Payments > Payments > Disputes
Find the disputed transaction and click on it
In the top right corner, click Accept dispute

After this, no further action is needed from you. The funds including the dispute fee of AED 110 will remain deducted from your account.

Challenging a dispute

If you believe that you have fulfilled your duties as a business and want to defend against the dispute, you will need to submit evidence to make your case. The card schemes will review the evidence and decide on the outcome of the dispute.

From your Mamo dashboard:

Go to Payments > Payments > Disputes
Find the disputed transaction and click on it
In the top right corner, click Challenge dispute

Provide details

Complete the details of the service provided
Always include a clear, short explanation of why the charge is valid in the Provide more details box

Upload supporting evidence

Next, you will need to provide proof that the charge was legitimate and that the customer participated in the transaction.

💡 Take note of the following when uploading documents to support your case:

Clearly label files e.g., "Proof_of_Delivery_Order123.pdf"
Supported formats include PDF, JPEG, and PNG
Each file size cannot exceed 20 MB
Group similar evidence into a single file using a tool like Smallpdf to easily merge files
Make sure you upload all the evidence you want to send before submitting. Once you've submitted the evidence, you cannot change the submitted documents or add more.

❌ The following will not be accepted as evidence

Audio/video files
External links or file downloads
Password protected files
Requests to call or email

✅ Evidence may vary depending on the type of dispute you are challenging, but general requirements include:

Proof of delivery/service (e.g. signed receipt, tracking)
Customer communication (make sure to include the email address or phone number of the customer in the screenshots)
Product/service description
Refund/cancellation terms
Device or login logs

A guide to dispute evidence

Below is a handy guide on what type of evidence is needed, depending on the dispute type and, crucially, what you need to prove in each case:

Dispute reason	What to prove	Examples of what to submit
Product or service not received	The product or service was delivered as promise	Delivery confirmation (tracking number, signature) Courier receipt showing successful delivery Screenshots or system logs showing access/use (for digital goods) Communication confirming receipt or no complaint Refund issued (if applicable)
Not as described	The item or service matched the description at time of purchase	Original product listing, service description, or promotional materials Signed contracts or terms of service Customer communication confirming expectations Photos/videos of the item before delivery Logs/screenshots showing service was rendered Attempt to resolve issue (support chats or emails) Refund policy and refund attempt (if any)
Unrecognized (customer doesn’t recognize the charge)	The customer engaged with you knowingly (e.g. placed an order, signed up, interacted with their site or brand) and the charge came from your business	Business name clarification Screenshots showing branding on invoice/website Service receipt or signed contract Order confirmation email
Fraudulent	The cardholder authorized or participated in the transaction	Signed receipts or contracts Login or account activity (e.g., access logs, customer ID) Customer communication acknowledging the charge Proof of delivery (physical or digital)
Cancelled recurring payment	The customer didn’t follow the cancellation policy or continued using the service after cancellation	Copy of cancellation/refund policy (highlight key terms) Proof the customer was informed of the cancellation terms Cancellation request (email, form, chat) or absence of one Usage logs after cancellation Signed agreement or subscription confirmation Refund confirmation, if applicable
Credit not issued	You completed the refund or credit from your side	Refund or credit confirmation Cancellation/refund policy Communication about the refund Reason credit hasn’t reflected yet (e.g. bank processing delay)
Duplicate	The customer was only charged once or any duplicate charge was refunded	Transaction logs showing unique transaction IDs Receipts or invoices showing single billing Refund confirmation for any unintentional charge Communication with customer about issue resolution
Incorrect amount	The charged amount matches what was agreed upon	Signed receipt or invoice with correct amount Explanation of currency conversion (if applicable) Communication showing agreement on pricing Refund documentation if adjustment was made
Other	The transaction is valid, and handled properly from your side The issue raised doesn’t justify a chargeback or is based on inaccurate or misleading claim	Clear written explanation of what happened Relevant evidence matching the customer’s claim (chat logs, invoice, contract, internal handoff emails, refund proof, etc.) Screenshot or documentation showing attempt to resolve the issue with the customer

Await the outcome

Once you've submitted your evidence, the issuer will review it and decide on the outcome. This outcome is final for all parties and we can’t contact the card issuer to appeal the decision or to seek additional information.

They can take between 30-90 days to get back to you with their decision. Once a decision is reached, the decision will reflect in your dashboard and you will receive an email notification.

Outcomes:

Dispute won: If the issuer is satisfied with the evidence you've provided, you win the dispute and the disputed amount will be returned to your account.
Dispute lost: If the issuer is not satisfied with your evidence, you lose the dispute and funds are not returned to you.
- At this stage you can proceed with arbitration if you want to argue your case further which will incur a cost of 500 EUR/USD depending on the dispute. To move forward with arbitration, let us know and we'll provide next steps.

While Mamo facilitates the submission of evidence to challenge a dispute, we are in no way involved in deciding the outcome of a dispute. Mamo doesn’t receive any information from the card issuer other than whether the dispute was won or lost, so we’re unable to tell you why a dispute may have been lost.

Refunds

Understanding disputes (chargebacks)

Suspended accounts

Understanding your Mamo receipts and tax invoices

Managing payment disputes in your Mamo dashboard

Responding to a dispute