I suggest throwing them out and re-ordering from TRR ....LOL...sorry...that was unproductive
I had the same problem with their headbands--some people told me to put them in the oven on low to re-shape them or use a heat "gun" to warm them up and re-shape. I just can't be bothered to put that amount of time and effort into something that still won't be as comfy as the "good" ones. If yours are only "stretched out" you're lucky...I had dozens that the ends curled OUT --they were completely unsalvageable (I bought 144...I used a couple of dozen and stopped after trying one on and realizing that they don't fit well )
Good luck! I hope you're able to figure out the "trick" to these!!