IMAP/SMTP authentication blocked – need mailbox reset

My Comcast email works when I log in through webmail, but all third-party email apps (Apple Mail on iPhone and Gmail) fail to connect and return “username or password is incorrect.”

I have already:

• Reset my password multiple times
• Confirmed I am using the full email address as the username
• Verified correct IMAP (imap.comcast.net, port 993, SSL) and SMTP (smtp.comcast.net, port 587, SSL) settings
• Toggled third-party email access off and back on
• Deleted and re-added the account on my device

Despite this, authentication continues to fail in all apps.

This appears to be an IMAP/SMTP authentication block or security restriction on my mailbox. Please remove any blocks and re-enable full third-party email access.