adding new conn on existing report didnt work

hi as you can see at https://community.fabric.microsoft.com/t5/Service/2-of-3-steps-done-for-non-expiring-id-in-pbi/td-p/4760335 we are exploring non expiring user ids in pbi.

we are lucky i suppose that i was able to change the creds on the conn of an existing/obsolete sql engine based report but before i did that i tried adding a new conn to the gateway for that report using our new non expiring id's creds .  PBI just jumped out of the panel where one does that and if i rememebr correctly left the old conn name as is.   i saw something about the refresh being disabled and the dataset must be fixed first but that seemed backward.   and i saw the same error when i successfully changed creds on the existing conn and everything worked anyway.

currently, in instance security on that user in server roles i have public and sysadmin checked.   to be honest, user mappings , securables and status dont mean anything to me in that same dropdown.   under the db, security , that user, i have db security admin checked under owned schemas, reader , writer and security admin under membership, and nothing under securables.   most of this seems irrelevant to me also if that id is alreayd sysadmin but who knows.

it seems to me we should at least understand this weird behavior because its eventually going to bite us at a more critical time.