1. INVOICES

Q. I need an invoice before making the payment. Is this possible?

Yes. If your university or institution requires an invoice before proceeding with payment, please contact us at info.iass2025@unam.mx / info.iass2025@fa.unam.mx, using the subject line: “Request for invoice before payment”.

Kindly include the following information:

• Institution/Company name
• Tax Identification Number (TIN)
• Billing address
• Amount and concept
• Required wording (if your funding program mandates specific text)
• Any other additional information you find imporant

We will provide an institutional letter that serves as a proforma invoice to initiate the payment process.

Q. How can I include specific billing details in my tax invoice?

During the registration and payment process, you can choose between receiving a conventional receipt (ticket) or a tax invoice.

If the standard tax invoice does not include the details required by your institution, select a conventional receipt (ticket) and proceed with the payment. After that, please contact us at the emails above, using the subject line: “Request for tax invoice with additional information”.

In addition to the specific details you need to include, please also provide the following information:

• Institution/Company name
• Tax Identification Number (TIN)
• Billing address
• Amount and concept

Important: Do not forget to attach your payment receipt.

Q. Can I ask for a tax invoice after payment?

Yes. Once your payment is confirmed, a recepit will be generated and display to download as a PDF document.

Please, notice that it may only be converted into a Tax Invoice within 72 hours from its issuance, in accordance with the regulations established by the UNAM Board of Trustees.

To request the convertion into a Tax Invoice, please contact us at the emails above, using the subject line: “Request for a reciept convertion into a tax invoice”, including the following information:

• Institution/Company name
• Tax Identification Number (TIN)
• Billing address
• Amount and concept

Important: Do not forget to attach your payment receipt.

2. PAYMENT ISSUES

Q. My card payment was declined, but I have sufficient funds. What should I do?

Declines may occur due to bank restrictions on international transactions. We recommend:

• Contact your bank to authorize the payment.
• Try using another card (only Visa or MasterCard are accepted).

If the issue persists, contact us at the emails above, using the subject line: “Payment processing issues”.

Include a breif description and a screenshot of your problem.

Q. The payment page shows an error (“Forbidden 403” or similar). What should I do?

Please try the following steps:

• Clear your browser cache or use a different browser.
• Ensure pop-ups are enabled.
• Attempt the payment again.

If the error continues, contact us at the emails above, using the subject line: “Payment error – Forbidden 403”.

Include a breif description of which part of the process the error occurs, as well as a screenshot of the issue.

Q. I completed payment, but I did not get a receipt. How can I confirm?

As soon as you completed your payment, a receipt must be displayed for download. In case it does not display or is not visible in My Account → Purchase History, contact us at the emails above, using the subject line: “Payment confirmation request”.

Include your name and the email you registed.

Important: If you are unsure, please do not attempt another payment immediately to avoid duplicates.

Q. After authorizing payment through my bank app, I was redirected to Mercurio platform. Was my payment successful?

As soon as you completed your payment, a receipt must be displayed for download (it must take few senconds, please be patient).

If you are unsure, please do not attempt another payment immediately to avoid duplicates.

Instead, contact us at the emails above, using the subject line: “Payment confirmation request”, and we will verify your payment status.

3. REGISTRATION ISSUES

Q. The “Submit” button does not work when I try to register. What should I do?

This issue may be related to browser compatibility. Please try registering using another browser (Chrome, Firefox, Safari, Opera, etc.) on a desktop computer.
If the issue persists, contact us at the emails above, using the subject line: “Registration problems”, including all the requested information from the Form. We will complete your registration manually.

Q. I cannot log in or reset my password. How can I access my account?

If “Lost your password” indicates that your user does not exist, please confirm you registered with the correct email address.

If the issue persists, contact us at the emails above, using the subject line: “Login/Password reset issues”, and we will reset your account manually.

Q. I cannot find the “My Account” section. Where is it located?

The My Account section is at the top right corner of the website.
Make sure you are registered and logged in. If you are not, you must first complete registration and log in with your credentials.

If the issue continues, email us with the subject line: “Login/My Account issues”, and we will assist you directly.