Sounds like either a new regulator or gear drive is in order...worn teeth will slip under high-torque conditions (like sealing the window shut).

It might not engage the window either until coaxed manually (as you have been doing).

At this point, it's hard to tell which until you remove the door panel and inspect. When mine caused trouble, the gear drive made noise, then one day seized.

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2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car