Can you hear the fuel pump when you hit the start button. Check fuse number 6 Krafftstoppe. If fuse is OK check the four pin connector to the pump, it resides under the RHR side of the tank. It is a known connection problem, clean with Deoxit. Fuel pumps can also seize due to lack of use remove and check with a 12 volt power supply. If seized they can sometimes be resurrected by soaking in vinegar for a week or two. After soaking apply 12v briefly and see if it is trying to move, alternating the polarity back and forth briefly will sometimes break it free. Applying 18v briefly can also sometimes work.
Regards Martin.