Gmail SMTP Email Sent with no errors but not received by recipient. Sent Email can even be seen in sent folder of the email account

Question

I am sending email using Gmail SMTP, the Emails are Sent with no errors but are not received by recipients. Sent Email can even be seen in sent folder of the email account.

The emails were being delivered earlier but are not now.

Also, how many emails can be sent via gmail smtp per day.

Answer 1

1. If you are setting incorrect password you will not get any error in sending an email but you will not receive the email if password is correct then there might be lots of reason. see this
2. Gmail Sending Limits