Click on the Settings (gear icon) in the top-right corner of the Chat interface.
Open the Google Chat app (or the Gmail app with Chat enabled) on your phone. how to unblock on google chat
Hover over the person you want to unblock. Click the three vertical dots (menu) that appear. Click on the Settings (gear icon) in the
In the left sidebar, click "Blocked" (you may need to scroll down). how to unblock on google chat