My local laptop is a Mac.
The ssh key is configured properly. This is the content of ~/.ssh/config
Host barthea
Hostname git-codecommit.us-east
On MAC, if above-mentioned tricks don't work, do the following:
Now try again. It should work. You may have to do it again next time as well when you face the error 403.
One of the possible reason for this issue is the keychain password different than login password on your MAC.