FSM - Field default value (integrated environment)

Hello SAP community,

I'm implementing FSM in an integrated environment. I'd like to set default values for the technicians when they will create their own Service Calls (ex: service call type). I'm unable to do such thing.

I've changed the default value in the code, can see the default value in the screen configurator but nothing on my smartphone as a technician.

It's actually working for a few standard fields such as priority but not for most of them.

Would you know how to define default values?

Many thanks