I agree with Tessy. Try to find out why you aren’t advancing. Is the horse you ride not able to go any higher/ become naughty if you do? Try to see if there is a horse that is a very easy jumper (that is able to jump higher) that you could ride for a few lessons to work on your position.
It can be really frustrating when you don't evolve as quick as you want to..
Can you identify why you are still in the same class after 2 years?
Is it because you don't have an easy horse who can go further quickly? Or because you change horses so you start from scratch whenever you change? Do you see improvements in your riding or do you feel there's a brake in you evolution? Did you talk about it with your trainer?
Maybe try to find answers to these questions, then once you identified the problem, search what you can really do to solve it (ride more, ride another horse, change your trainer,...)
Hope it helps, good luck and don't give up on your passion 🙂