Please persevere and I'm sure you'll get this booked in.
Perhaps the phone call was lost hence why it cut off.
Other alternatives could be to visit a Samsung Service Centre or if available in your region and for your model of phone check to see if you can book a Doorstep Repair Service from Samsung.
I wish you all the best with this situation. @nico81arg
Current Phone > Samsung Z Fold³ 5G.