Non shingles rash following the shingles vaccine

I took the shingles vax at the end of November 2025. Around or just pas Christmas I developed a severe red rash all over my body. It was itchy and my body was flushed all over. Face was not affected. I tried Prednisone and reactine which is a anti histamine. I also was told to use steroid ointment all over my body. The rash seemed to improve but not clear. Now near the end of feb 2026 the rash has not abated and is getting worse. The skin is very sensitive to my finger nails and flushed red. The itch occurs in various areas but seems to be controlled by the extra strength lotions I am using. The dermatologist seems to think its a shingrex vaccine reaction. It is the only change I have had in my day to day. Has anyone had this reaction and if so what did you do? Thank you in advance