@Mohan s, Thanks for posting in Q&A.
From your description, I know you got an error when accessed a deployed app by you.
Based on my research, there error message means failed to detect a required app protection policy for the app.
To clarify this issue, please follow the link below to check whether you have met the prerequisites for deploying app protection policies and whether the app protection policy was applied to the app successfully.
Please check above information, if there is any update, feel free to contact us.
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