Constant errors with views, data, and updates. MyChart w/other hospital systems runs perfect. Multiple contact with Mt. Sinai MyChart support - clueless. My Mt. Sinai docs - just as frustrated. They also can't see test results, visit notes, and video visits are abysmal, *only* with Mt. Sinai MyChart. I successfully use MyChart w/4 other networks. I've switched 14 Mt. Sinai docs to ones in other networks because of this. 2 Mt. Sinai docs left. Soon, I will not use Mt. Sinai at all. Fix it.