Have you checked your vitamin d level? If you are taking supplememts of D and its high it can affect calcium absorption and cause that to be high as well. Treatment for that is to cut down on vitamin D.
If you have recently had a blood test done that has showed a hi calcium level, then it would be wise to get another blood sample checked to make sure that it is correct.
There are a number of reasons for hi calcium in the blood.
Your doctor should be able to advise you further.