Thanks for posting.
It seems the most probable reason that this issue is happening due to old cookies stored in the edge browser for this respective account which is causing conflict.
In an InPrivate window there is no stored login info (cached credentials in this case), hence its working fine through it.
You can try to access the portal with a fresh login after you delete the cookies.
Please follow the give steps to achieve this,
- Open Microsoft Edge and go to Settings > Privacy, Search, and Services.
- Under Clear browsing data, click Choose what to clear.
- Select Cookies and other site data and Cached images and files.
- Confirm the action to clear this data.
It's also a nice practice to use different profiles for different accounts in a browser to avoid any such conflicts.
Plese try it out and let me know.
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