Amgevita by any chance? I spent 2 years with methotrexate and it was killing my liver, so I was switched to Amgevita. Took literally days for me to feel the most pain free I can remember.
You really need to demand more from your GP, or change altogether, or if your work offers a health cash plan or online GP services perhaps try those routes.
Personally I believe that diet is definitely a factor, but for rheumatoid and psoriatic these are autoimmune, so very difficult to find out what foods are actually causing the issues and sometimes we find ourselves popping a ton of herbals with no real gain.
It took 10 years for docs to figure out my issue - I was in chronic pain for years to the point of being unable to sleep as any movement would cause me to wake up almost screaming. The belief was that I'd ruptured/torn MCL's and they weren't healing or scar tissue was causing friction. I was told not to do the majority of things I enjoyed (skiing, weight lifting). I was on 240mg of codeine and 400mg of tramadol a day. I gave up on the NHS (as much as I fully support it and believe it is being deliberately underfunded). Eventually I went cold turkey on the tramadol (big mistake) and cut my codeine intake to only when required on really bad days. 3/4 years ago I got fed up with my toes being messed up, went to the docs and she said it's likely psoriatic arthritis. Got booked into the rheumatology clinic a few weeks later, x-rayed all over and it was confirmed and they started me on methotrexate. COVID hit and understandably it was difficult going to get this dosage right, but it was never working out. Last year I started on Amgevita and within days the psoriasis across my body reduced by 90% as did the remaining aches and pains. I'm 34 now btw, there was never any real support because no one even thought it could arthritis as my family history only included osteo in the older generations and I had no signs of joint wear. I tried all forms of diet changes, losing weight, supplements. Nothing ever really made a proper dent in the issues.
Moral of the story - tell the GP surgery you need to see one of the docs with a background in all things arthritis, and then whoever you end up with, push for a referral. The arthritis specialists aren't in our GP surgeries.