I had the same experience. Therapist says partially due to Some scar tissue and layers of fascia that “fuse” together. My therapist has utilized MFR techniques. Cupping, other suction type devices, and finally just digging in with “scraping” tools. I’m also utilizing my stationary bike 40 minutes per day along with my therapy homework. Keep at it, I’m 7 weeks MUA and just reaching 120 on my own. Still have stiff feeling but starting to break up. I finally feel like I’m turning the corner in a positive direction just this past week. Hang in there. The hard work will pay off.