I registered an app in the tenant that allows personal account login, and then use the personal account to log in to test, it works fine for me, please refer to my operation process:
Create an application:
Get the authorization code:
https://login.microsoftonline.com/common/oauth2/v2.0/authorize?
client_id={client id}
&response_type=code
&redirect_uri=https://jwt.ms
&response_mode=query
&scope=User.Read offline_access
&state=12345
Redeem an access token and refresh token with an authorization code:
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