How do I solve a door knob “catch” problem?

Did you check your hinges? When we bought LuckyHomeToday, some of those bathrooms had a similar issue. I had to re-tighen and replace missing screws to fix it.

Sounds like the door wasn’t installed properly. You’ll need to remove the casing (trim around the door). When you remove it you can see how (or if) it’s shimmed. Once you do put a level on it (at least a 4’ level) and see if it’s plumb. To do this you put the level against the side of the door frame where the catch meets the frame. Next check the other side. If either side is out of plumb you’ll need to either install or remove shims between the 2x4 and the door frame. Put or remove enough shims to bring everything plumb. If everything is plumb the job just got harder. You’ll need to remove the top of the door frame and cut off a little at a time, make it plumb and test to see how it closes. Do this until you get the desired result. This part is best left to a professional.

I would tighten the door hinge plate first, usually the top one. If the screws are stipped you can add either a match or 2, or even take the plate off and insert a glued wooden dowel and then put the screw back in.

If the latch itself is the problem.... https://www.youtube.com/watch?v=UcWRcbK4Ra4

Also check the two pieces that actually fasten the door, the striker and the plate. The plate is the slightly curved metal on the wall side of the door casing. The striker is the piece on the door that you can push in with your finger. Now, investigate! Are these pieces engaging? The striker should start pushing in as it hits the plate, then stick out fully when it matches up with the hole in the plate. That action is what fastens the door. Several things you can do. Oil the striker. Move the plate and enlarge the hole in the wood. Anyway, your figuring out the problem is the key to fixing the problem. Good luck!