I have created a Lockdown screen for Android, but i am unable to get the phone app working; i have tried setting it to Launch various phone apps com.android.server.telecom, com.samsung.android.incallui, com.android.phone but i always get the package unavailable message; if you go via the contacts however you can dial out and you can also dial out via bluetooth and the phone will still receive incoming calls.
I'm running Mobicontrol 14.0, and the phone is Samsung SM-A520F Android 8.0 with agent version 13.5.0 build 1327 (ELM)