I have suffered with restless legs since I was a child but it comes and goes and gets worse when I am pregnant. Recent advice I had was to cut down on caffeine and raise legs when going to sleep or pop a pillow in between your legs if you sleep on your side. Sorry this isn't much help, still trying to find a cure myself but I totally feel your pain. It's horrible not being able to sleep
I had this with my last pregnancy, normally if I was over tired. It normally started just before bed. The only thing I found helped was to go for a walk with the dog around the block. Bit of a pain at 11pm but it worked and it kept the doggy happy too!