I am sure this isn’t your problem, but I got a new unit last October.
Came home from vacation yesterday and house was 80 and could t get colder.
Outside fan was running, but the copper going into the house wasn’t cold at all.
Turns out the installer way over charged the system.
They came out and captured a few lbs of puron.
Case closed.
So it can go both ways, over or under charged, bad fans and bad or weak capacitors.
My money is usually on throwing in a “hard start” capacitor kit if the unit is 5-10 years old and doesn’t want to get going.
Especially if it’s never had a replacement start capacitor.
Another tip- excessive condensation in the drip pan can be low Freon / a leak