That's a pretty old model indeed.
If it stopped working with a computer you know it did work with before. Does it work in any other programs? Because if so it might be Clip Studio that isn't working correctly.
And if it doesn't work on a computer that you know it did work in before, it might be that the tablet is showing its age and, unfortunately, is starting to break.
Apart from that, try reinstalling the driver indeed and if nothing fixes it, might just be time for something newer.