To ensure that Profile1 applies to Device1 only, you need to modify the Applicability Rules in Profile1. You can use applicability rules to filter which devices receive a profile based on criteria such as device model, manufacturer, or operating system version. You can create an applicability rule that matches Device1’s properties and excludes Device2’s properties. References: https://docs.microsoft.com/en-us/mem/intune/configuration/device-profile-assign#applicability-rules