GE washer not filling on c/c

Washer Repair
1

GE washer not filling on the cold/cold setting. all other setting work well. replaced the temp switch and the inlet valve and didn’t fix it. even changed out the timer just for grins. i looked at the cold water hose to check for debris in the screen. nothing. sooo. any ideas?? I’m in residential maintenance and the apartment directly above (1st and 2nd floor) is doing the same thing.