@Ramya Reddy Thanks for posting in our Q&A.
For this issue, it seems that there is a conditional access policy to block the access. To clarify this issue, we appreciate your help to collect some information:
1.Please check if there is a conditional access policy deployed to your user. If yes, please check if the setting "Require app protection policy" is select under "Grant" in this policy.
2.Based on my research, app protection policies' supported apps are listed in the following article:
Your app is not listed in this list.
If there is anything update, feel free to let us know.
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