I've recently been given a hard contact to wear and with it regained a little sight.

The problem now being in that I put the contact in and as soon as I blink it moves.
It was fine when I had it fitted at the hospital and it was fine the next day when I put it in, but since then it has been misbehaving.

I have tried refitting it numerous times, on different days but with the same results. So much so I am sure I can't be putting it in the wrong place and I'm certainly not putting it in the wrong way around.
Has anyone else ever had this problem. Is there someway around it or do I have an ill fitting lens that needs replacing? I will call the hospital up on wednesday but first wanted to hear any advice for those with more experience with contacts. As a newbie contact wearer perhaps there is something different I can do to solve the problem.
Many thanks in advance.