If you pull out or try to push in the foot rest
with the slideout in, that raises the sofa up higher than what it is if when the slideout is extended. You have to lift the foot rest up & make sure it is over the 2 fingers. When latching the footrest, have the release latch operated until just before latchup.
I sleep on the sofa every night, so I do this everyday! You don't know if the footrest is latched, unless you are on the move.
I can't say I get mine latched everyday. Sometimes it has to be lifted up to latch also. It has to slide just right on the tabs to latch. Holding the latch, just makes it slide easier.
Although our coach is older the locking mechanism for the foot rest may be similar. We had a problem a while ago and found the locking mechanism started to loosen from its mount. The lock rod would no longer fully extend through the base plate to lock the foot rest in place.
Ours has a flexible cable running from the actuator to a detent rod. The rod and bracket assembly are about 18" behind the front panel of the foot rest. The assembly is held in place on the sliding portion of the foor rest by 2 bolt and nut assemblies.
You may have to fully extend the rest to see the locking assembly.