I Have Been Experiencing Muscle Cramps For Two Months Now

I have been experiencing muscle cramps for two months now , in my legs ans arms and shoulders and sides . I have been to the doctor and they suggested hylands leg cramp remedy , more hydration and magnesium and pottasium supplements ,. I have been taking magnesium and pottasium supplements for years now , calcium also . I drink powerade and water during the day . I have been experiencing allot of neck pain in the base of my skull and have been going to physio therapy , but it doesnt seem to help . I am a letter carrier for 24 years now .