Hi @nbarsley1 ,
Do you mean that one user in your talent could not connect with Access SQL, but others can?
Please check whether this user's license is expired.
Only premium license(per app/per plan) could connect with Access SQL.
You could ask him to check his license here:

The admin could check all the people's license in office 365 admin center.

You could check whose license is available, whose is unavailable.
What's more, please check that user's the Azure SQL Database firewall whether allows the connection request from powerapps.
I believe the main problem should be about license or firewall.
If the problem still exists, please ask him to try another browser, update browser to latest version, clear the browser's cache.
Best regards,