This is the config how to block MAM config on Android Phones.

Go to https://endpoint.microsoft.com/

Endpoint security > Conditional Access

Create new Policy

Give it a name like No MAM – Android

Select Users or group or all.

Select Cloud apps Office 365.

Conditions -> Device platforms = Android

Filter for devices -> Rule syntax
device.operatingSystem -eq “AndroidForWork” -or device.operatingSystem -eq “AndroidEnterprise”

Grant = Block Access
Enable Policy.