My emails are not sending from Outlook

[premain]

At 8am this morning, I was no longer able to send emails from my tpg account using Outlook. I am still receiving emails. Please see attached error email. I am able to send an email from the TPG post office.
"

Your message did not reach some or all of the intended recipients.

      Subject:     testing101

      Sent:  27/11/2020 6:06 PM

The following recipient(s) cannot be reached:

Please advise, how to fix this issue

[david64]

Hi premain.

Is the ip address in the error message [203...] your current address? It might be that gmail has flagged that ip address as bad.  Have you sent other emails to this person recently or not for some time. Your ip address may have changed in the meantime. You could reboot the wifi router and get a new ip address, or stick it out and see if gmail resets that address at their end.