Not enough practice and proper scope set up.
Yep, practice is number 1.
I’ve hunted rabbits and squirrels with .22lr, usually CCI Stingers or Mini Mag, since CCI first appeared, other ammo before that. And with a .22 pistol.
Give yourself a rule. Or challenge if you want.
You cannot use that gun to hunt until you can hit a playing card 10 shots out of 10 every time, at 30 yards. My target in 1973 was a matchbook cover. 10 shots at 30 yards every time. With a Ruger Single Six .22 revolver. I hunted squirrels with it. I usually sight in a .22 rifle at 50 yards, the .243 at 150.
I use a Marlin 925 bolt action .22 now, Tasco 3x9 scope. With CCI Stingers it will hold a 1 inch group at 30 yards every time. I also snagged a pair of see thru scope mounts a while back for $1, resale shop. That lets me use open sights too. I’m not near as accurate these days, I think I held a 3 inch group with open sights. Really bad for me. I could once hit a matchbook every shot.
Note the last picture in that article. They used a cross pattern I’ve known and used for years. That same spot is good for most large animals, and for deer, aim for the base of the ear.
Before they made rimfire illegal for deer, my grandfather killed dozens of deer with .22 short, hitting them at the base of the ear. He could literally light matches with his .22 rifle. He required that kind of accuracy, my father did too. Miss and you were in trouble. Ass whipping time. And he knew how to use a belt lemme tell ya...Before I could hunt, I was required to hit a .22 cartridge box 10 shots out of 10 at about 30 yards. For a 5 year old kid, 30 yards is a good starting point. I went in the woods at age 9.
I recently got a Heritage .22/.22 mag revolver, 6.5 inch barrel. 1st time to fire it, at about 20 yards it held a 3 inch group, 17 shots. And that’s horrible, for me. 30 years ago I practiced on playing cards. Never missed, ever.
At 9 years old (barely) I was also able to disassemble, clean, oil and reassemble every gun in the house. Winchester model 12 pump 12 ga, Remington 512 single shot 22 rifle, single barrel 410. And it BETTER work right. In the woods you get one chance. Gun cleaning was my job soon as we got home every time, no exceptions. And everything got cleaned twice a year, even if it had never been touched. I still do that. Just cleaned my 16 gauge, haven’t fired it in 10 years.