That is a flex plan. An HSA is different. With my HSA the account is actually in my name, it goes with me wherever and whenever. Can be used for nursing homes even when you get old. A flex plan is where they put a bunch of pre-tax money aside and it's a use it or lose it. I'm surprised you were allowed $6000, the ones I've had available they wouldn't let us go that high, it maxed out much lower than that.
It was for a family, not just me.....................