You don't say if you're trying to listen to DMR Repeater or simplex comms....the BCDx36HP models aren't very good at decoding DMR simplex, but the following steps should work for both, to at least get you started
Go to MENU > Srch/CloCal Opt > Digital Wait time set to 400ms, Digital Threshold set to Manual, Digital Threshold Level set to 5.
Come out of that menu tree (several presses of MENU).
The scanner will likely be either then be scanning channels or be holding on a channel. If it's scanning press CHAN/MOD.
Type in the freq of the system you want to listen to followed by CHAN/MOD.
Check that modulation = FM (FUNC+CHAN/MOD until it cycles through to FM).
If your setup is right, you should see DMR type being decoded, Slot number and when there is voice on the system, it should decode and show Color Code/ TGID and UIDs in use.
Does that work?