Hi @Nguyen Van Duc 1 (CMC Consulting)
Teams tag is mainly focused on the general issue of Microsoft Teams troubleshooting. According to your description, your question is not in our support scope. The following suggestion is for your reference:
- Please upgrade the Microsoft Teams PowerShell module: Make sure you are using the latest version of the Microsoft Teams PowerShell module, refer to this reference.
- Please verify user permissions: Make sure your account has the appropriate permissions to execute the Get-CsApplicationAccessPolicy command. Verify that you are one of the administrators and that you have verified the policy correctly?
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