I have heard of this happening after COVID. Though it may not be common - it does not mean it does not exist - as you are living with this. I had developed some hearing loss and tinnitus in one ear. I was able to get a hearing aide which helped the hearing loss, but was able to muffle the tinnitus. This may be something to look into, as tinnitus can be very disconcerting. Of course, when the hearing aide comes out at night-time, the tinnitus can be so loud and interfere with sleep. Look into a hearing aide - this may help. Good luck.