It’s stretchy? Knits tend to do that. Sometimes you can fix it by trimming off the selvedges — assuming it’s the selvedges rolling and assuming they weren’t already trimmed at the factory — but not always. You can try stabilizing the edges with starch or gelatin, although I’m not sure I’d want to do that with a velour. Otherwise, the best thing you can do is try to work around it by not using the edges.