How to connect credentials to Salesforce Custom Domain?

Describe the problem/error/question

Unable to create credentials (oauth) for salesforce sandbox with custom domain

What is the error message (if any)?

error=redirect_uri_mismatch redirect_url_must_match_configuration

Information on your n8n setup

N8N self hosted. 1.117.3
Have tried the callback url from the instructions and the one shown on the creation screen, same result
Note url shown in pop-up below can’t be amended.

Did see this thread from a year ago but no answer?