Problem: Cupcake Liners

Hello! My first blog. I am a newbie home baker.  Why do  cupcake liners crimp up in the muffin pan after you fill with the batter.  What can I do?  I think it looks tacky.  Do yours do this, and you just go right on or.... The only ones that don't are the foil lined which I did find a cute black and white that was foil lined. So much prettier.  I found some red and green foil ones by Reynolds today.  Pretty and won't have that problem.  But, I have so many that I bought when getting started and I'm sure they will crimp.

Thanks!!!