Cleaning
I would, as suggested, give it a good cleaning. Clean the chamber, but also clean the extractors. Dirt gets into the grooves and makes the extractor ride too high to get a good grip.
It could also be a weak extractor spring, or possibly the extractor has a burr on it, or maybe broken a bit at the tip. It is also possible that when made, the extractor is a bit large on the bottom of it (the hook side) and needs to be slightly cleaned up or filed a bit so it will allow the extractor to go a bit deeper to pick up the empty.
Another possibility is that the hook of the extractor is not allowing the rim of the cartridge to fully seat against the breech block. This might make the extractor ride a bit high and not grab the rim properly. In other words, it might need to be slightly filed to make sure it comes down to grab the rim, but still have a bit of clearance. Rim thicknesses in .22 ammo can vary a few thousands being thicker or thinner.
However, the probable cause is a lot of .22 Shorts or Longs fired in the rifle. If the front edge of the chamber has a bit of a lip on it, then lead from a shorter 29 grain Short or Long can be shaved off by the sharp lip of the chamber, and leave a bit of lead or powder residue there. When you chamber a Long Rifle, this residue creates a tight spot, and grabs the case. Use a good bristle brush, preferably brass or synthetic bristles and not steel or stainless steel ones, and put it into the chamber end. Rotate it by hand pressure only, don't power it with a drill or something else. Use a good solvent.
