Error 401

Good Day,

When I click the link to grant permission to google I get an error message:

401. That’s an error.

Error: invalid_client

The OAuth client was not found.

Request Details
scope=https://mail.google.com/
response_type=code
access_type=offline
redirect_uri=http://facs.schools.lc/wp-admin/options-general.php?page=postman
login_hint=fondassauprimarygmail.com
approval_prompt=force
state=e254457f7497c00fbb0d2bb4ac36487b
client_id=facsschoolslc
That’s all we know.

Please advise

https://wordpress.org/plugins/postman-smtp/