Hi @juanmigueldoton
Dropping a phone certainly doesn't so it much good.
It may be that the volume problem is caused by a loose or faulty power and volume flex cable (part # GH81-20712A) or perhaps a faulty [https://www.sunsky-online.com/p/EDA005594669A/For-Samsung-Galaxy-A22-5G-SM-A226-10pcs-Power-Button-Volume-Control-Button-Black-.htm?gclid=EAIaIQobChMIi478gr_mgQMVhGoqCh3MMQIbEAQYByABEgLcGPD_BwE|power/volume control button] (supplier example only to show the button)
With regards to the other problem you're having with the headphone jack, it could be a faulty headphone jack. There's an internal spring that signals the audio control when a plug has been inserted into the jack so perhaps its intermittently operating when it shouldn't be. If this is the case then the jack would have to be replaced as it cannot be repaired. The good thing about this is that the jack is on the charge port board which is a separate module so it's easy to replace once the phone is open. The part number for the charge port board is GH81-20699A.
To find suppliers for the parts search online using the part number only. Couldn't find a part number for the control button so if it is faulty search for ''Galaxy A22 5G power/volume control button.''
Here's a teardown [https://www.youtube.com/watch?v=ev71VWUAkjU|video] for the phone which may help.