I used to have problems with peeling cases but I do the following and have not had any problems since:

I use good quality cases – I found I had far more peeling cases when using cheaper brands

I let my cupcakes cool down in the tin rather than removing them to a wire rack, this again seems to reduce peeling.

I always store the cupcakes in a cardboard box or tin.  I found that keeping them in a plastic container such as a Tupperware box used to make them peel

Hope one of those suggestions helps

I use heavy duty greaseproof cases from design-a-cake. usually mine peel when my cupcakes are too soft.

quote from hummingbird

My cases keep peeling away from the cakes. What is going wrong?

The only supermarket cases Ive had  so far that haven’t peeled are morrisons foil ones.

I also had this problem, and now, before they’re placed in the oven, I use the end of a teaspoon, and swirl the mixture around in the paper cases…don’t know how this works, but not had the problem since LOL