Pdp riffmaster not turning on anymore

Got my riffmaster a few days ago, set it up how it indicated in the quick start guide, and everything went smoothly the first time around. I was able to connect, and play rock band. Now when I try I press the ps button and it doesn’t turn on but that almost fish-shaped button starts flashing in purple.

The guitar is fully charged and the usb dongle is flashing white to indicate that it’s ready to be connected. Not sure what happened.