Thanks for the question. If you develop rash over the bracelet area, it is possible that you may have an allergy to the material of the bracelet e.g. nickel, leather etc.
This is called an allergic contact dermatitis.
A way to determine if you have a contact allergy is to do a patch test. When doing a patch test, tiny chambers containing different ingredients are placed on the back for up to 48 hours. A reading is done on the following day to see if you have a reaction to a particular ingredient, which will confirm the allergy.
You can see your dermatologist who can advise you further on the test.