Havr lost my voice however have no pain why does this keep happening 2 to 3 times per year?

Laryngitis inflammat. When laryngitis occurs without pain, consider an irritation that comes and goes -- the most common are voice overuse and reflux of acid from the stomach into the voice box, causing swelling.
Laryngitis. Usually when you loose your voice for a few days with no other symptoms this is a case of laryngitis. There is inflammation lower down in the trachea although no pain. The best thing to do is rest your voice and it will improve in a few days.