you have way too much moisture in your house,, and should consider a de-humidifier!! your freon is NOT low or the filter would not freeze!! only theoutlet pipe shows sign of ice when freon is low,,,, your air is really cold to be freezing the filter moisture!!

generally this is because
1. dirty filter
2. low freon charge

It’s getting water from the condensation dripping onto the filter. I imagine that the back of your air conditioner isn’t tilted downward slightly to allow the water to drip sufficiently out the end of it that is sticking outside. If you fix this then you shouldn’t have a problem anymore.

Ice on the filter means it is dropping off of the evaporator. The filter could be dirty. If not, the evaporator could be dirty and needs to be cleaned. Or the system could be low on refrigerant.

It needs to be cleaned or replace it happens when there’s too much junk on it and the condensation on it freezes.