The issue was quickly resolved by Gmail support.
Here are some Gmail issues that Gmail Support perfectly addresses:
Gmail account sign-in issues
Resetting your Gmail account or forgetting your password
Fixed issue sending and receiving email.
Gmail account hacked or locked out issue
Fixed spam, junk mail, and email filtering issues.
IMAP and POP3 configuration issues
Troubleshoot Gmail account setup issues on your Android or iOS device
Gmail connection error and many other issues