Many palpitations everyday, ekg. holter monitors, 30 day event monitor, all normal but they all do show many palpitations but no arrhythmia. why?

No such thing: Palpitations are a symptom you feel, and cannot be recorded by any machine. The event monitors and holters would record extra heartbeats called pacs or pvcs, both of which are a type of nonsustained arrhythmia, but which can certainly lead to palpitations. You need to check in with a cardiologist or electrophysiologist who can help you correlate your symptoms with your heart rhythms.

Thanks for asking!: Normally contractions of the heart are initiated by a special collection of cells called the sinus node. However, virtually every cell in the heart has the ability to start a contraction. Some people have cells in the heart that initiate a contraction instead of waiting for the signal to come from the usual place (the sinus node). This creates an extra beat, experienced as a palpitation.