What could be the reason of periods delay after accupuncture?not active sexually but got periods after 50 days and after 2 accupuncture sessions.

Too general.: I am sorry but there is not enough information here to provide you a useful response. Don't know if the acupuncture was focused on treatment of gynecologic problems, for fertility or if it was for a multitude of other medical issues.

Change in hormones: Not sure what you were having treated, but it is possible the acupuncture could have made an increase in your hormone levels temporarily changing your cycle. It may be a coincidence also. We do know that when you are stressed, this can change your hormones and delay your period from starting. It isn't harmful.