What is causing an itchy neck rash??? 3 Office Visits and unable to cure???

[provlima]

I am a 70 year old male with no underlying health problems

Have had a chronic itchy neck rash for a year. My dermatologist has been unable to successfully treat it
First possible diagnosis was possible soap or shaving cream allergy . I have used both a safet razor as well as electric shaver with the same results. I also tried hypoallergenic soap and shaving creams with no results.
The second possible diagnosis was an allergy, this time treated by tapered prednisone tratmen for 12 days.
The prednisone seemed to help but on the 10th day of tratment the itching returned.
Now my doctor has advised using Triamcinolone Acetonide cream on the rash twice a day, but after 5 days still no success.  Has anyone had a similar problem and found what the solution to curing it was??? Thanks for your help!