Unable to Configure Email Setup for digital-signaturecertificate.com on Vercel

[balarajubhighermatrix-ui]

Summary

Hi Vercel Community,

We are building a website digital-signaturecertificate.com
(Next.js app) and deploying it on Vercel. Our main issue is with email notifications.

What we are trying to achieve:

When a user submits the DSC application form,

The admin email ([email protected]
) should receive the applicant’s details.

The user should also receive a confirmation email saying “DSC Application Started” with a Proceed to Payment button. The payment URL is dynamic, based on the product (type, validity, price).

If email fails or the user cancels, they should get failure/cancel notification emails.

What we have done so far:

Set these environment variables in Vercel:

SMTP_USER = [email protected]

SMTP_PASS = (generated Gmail App password)

PAYMENT_BASE_URL = https://digital-signaturecertificate.com/payment

Created an API route (/api/submit.js) to handle form submission, using Nodemailer with Gmail SMTP.

Issues we are facing:

No emails are being received (neither admin nor user).

No error logs are visible on Vercel dashboard for this function.

Not sure if the configuration for Gmail SMTP on Vercel is correct, or if we need to use a different email provider (like SendGrid, Postmark, etc.).

Questions:

Is Gmail SMTP reliable for production use on Vercel, or should we use another provider?

Do we need any extra configuration for environment variables (like encoding special characters in Gmail app password)?

How can we properly log/debug API function failures on Vercel?

Can anyone share a working example of Nodemailer setup on Vercel with dynamic email templates?

Any guidance or working example would be greatly appreciated 🙏.

Thanks,
Team Digital-SignatureCertificate.com

Additional information

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Example

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