Not recieving otp mails eventhough Iam getting the mails correctly in localhost

[SaiSruthisri]

Recently I got a pr merged , in which I have implemented a functionality to send OTP's emails to the user for otp verification before signup/login.
I have used Nodemailer to send emails.
I've set the env's needed for it too i.e

 EMAIL_USER=your_email@gmail.com
 EMAIL_PASS=your_app_password

gmail acc
google app password after 2 Step verification

Everything is working fine in the localhost , even after my pr got merged all other stuff I have implemented in that PR were working ,OTP window was opening , but OTP emails are not being sent in deployment.
Even the PA tried to run it in his localhost everything was working fine ,otp emails were coming but why are the gmails are not being sent in the deployment is what I am not understanding.

The project backend is deployed on render , frontend on netlify.

Is the issue in the Google blocking nodemailer from using gmail? , Or any other permissions need to be given in deployment?
Can anyone help me out in this I can link PR for review if needed.