Stacked Matag washer & Dryer (Dryer on ...

Opening door while spining should stop the machine.
Since no water comes in, the agitate stage will not work even when the timer will be on this spot.
Check first the filters on the inlet water line (both sides).
Then, if problem still exist - check that the inlet water valve works(it is an electromagnet valve, located at the pipe's entrance to the machine)).
If it doesn't work, test that it get power. In case it get power and doesn't work - You can easily open the valve and clean it (from scale or other dirt). Be aware you should disconnect the power cable from machine before doing it !!!!
Check as well for valve's coil resistance. In case you have no resistance measurement - you should replace it for a new one.
Good luck !