Information
You should require your users to use a complex password with a at least two character sets (letters and numbers, for example) to unlock their mobile devices.
Rationale:
Devices without this protection are vulnerable to being accessed physically by attackers who can then steal account credentials, data, or install malware on the device.
Impact:
This setting will have a moderate user impact
Solution
To set mobile device management profiles, use the Microsoft 365 Admin Center:
Under Admin Centers select Endpoint Management.
Select Devices and then select Configuration profiles
Select Create profile
Set a Name for the policy, choose the appropriate Platform and select Device restrictions
In the Password section, ensure that Required password type is set to Alphanumeric.
Default Value:
This setting is not enabled by default.