unusual actions tortoise hiccups

My tortoises always looking like it has hiccups or is trying to swallow something. It seems to be almost a habit. I is a herman tortoise of only two years, i is given fresh water and fresh veg everyday and is bathed everyday too. Its bedding is made of hemp.

There is no other signs, eyes and clear no froth or liquid from the mouth.

what would coz my tortoise to do this??


Many thanks