I used a stone cleaner that contains hydrofluoric acid on a polished granite and it etched the surface. I thought acid will not effect granite?

Acids generally will not harm granite but hydrofluoric acid is the exception. Hydrofluoric acid will etch polished granite as well as glass. Never use HF on polished granite. Read MSDS and label directions.

FYI Hydrofluoric acid is a common chemical found in many stone cleaners. HF is designed to be used on sandstone exteriors and should never be used on polished surfaces.