Simple endometrium cystic Hyperplasia w/o typia

On the 31st, I had my tubes removed and due to not being able to perform an endometrial biopsy In the office due to a cervical stenosis, the doctor performed that while I was under as well. I have a retroflexed uterus and have been experiencing lots of cramping and pain on my lower left side. My doctor was thinking it was due to the placement of my Mirena IUD (I have used this BC for 12 years) and now my uterus was shaped.

I got the results back from my biopsy and it says that I have Proliferative endometrium with simple and cystic hyperplasia without atypia. When I was looking online about different treatments the main one was having an IUD, but I’ve already had that for 12 years and still experiencing pain. Has anyone been diagnosed with this, What treatment plan worked best for you?