My SanDisk Cruzer Switch 32GB USB isn't working.

It was working fine yesterday morning on a Windows computer and then again yesterday evening on a Mac but later on a different Mac and then on my Macbook it wouldn’t work.
When I plug it in either, nothing happens or, I get an error message saying that it can’t be read. It cost me €30 and I only bought it a couple of weeks ago so I don’t want to dismiss it without trying to get it working again, plus it has a fair amount of college work on it that I did yesterday and didn’t get to back-up onto my laptop.
Any chance of there being something I can do to fix it? Or at least recover all my stuff.

If you’re yanking it out without doing a Safe Removal option, at least on the Windows machine,s the device’s File Allocation Table could be screwed up.  If the files are important I suggest you find a reputable local repair shop to see if they can save them for you.