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 |
|
Not as described | The item or service matched the description at time of purchase |
|
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 |
|
Fraudulent | The cardholder authorized or participated in the transaction |
|
Cancelled recurring payment | The customer didn’t follow the cancellation policy or continued using the service after cancellation |
|
Credit not issued | You completed the refund or credit from your side |
|
Duplicate | The customer was only charged once or any duplicate charge was refunded |
|
Incorrect amount | The charged amount matches what was agreed upon |
|
Other |
|
|
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.
See also: Understanding disputes, and Managing disputes in your Mamo dashboard