H.S.
When my daughter was between 3 and 4 she chewed excessively on her fingernails. I spoke to the pediatrician, and she said to completely ignore it. We did, and she stopped doing it within a few weeks, started it up again, and stopped again.
Not sure how long your daughter has been doing this, try to wait it out patiently.
Maybe you can help her by NOT BUYING new clothes, just explain that she will have to wear these until they don't fit anymore. But I would only do this if you think your daughter chews on clothes to get your attention.
Sometimes kids would love to stop their annoying behaviour, but can't help it. And then it would be pretty devastating to your daughter.