Outlook prompting for credentials after migration

Question

Good day all i'm currently experiencing a strange issue with Outlook being prompted for Username and password after migration.

The strange thing is if i use the new SaRA tool - SaRACmd.exe -S OutlookEmailSetupScenario -AcceptEula

It says there are no issues, and it creates a new profile just fine, but if i try to load the old profile it keeps prompting

Secondly, if i use HKEY_CURRENT_USER\Software\Microsoft\Exchange (AlwaysUseMSOAuthForAutoDiscover set to 1), then create a new profile or use the existing one, then it prompts for credentials and connects just fine.

Thirdly if i cancel the Outlook login prompts on the original profile, i'm met with the "Allow this website... " autodiscover message, which if i Allow doesn't do anything and just fails.

The Outlook version is M365 Apps Microsoft 365 MSO (Version 2408 Build 16.0.17928.20336) 64-bit

Windows version 22H2 19045.5371

Its in Classic Outlook Mode

Autodiscover still points to Exchange 2019 CU14

Any ideas? Thanks