Scooter no longer starts after gas pull-off

Hi, I was still working on the gas train throttle with my Piaggio NRG MC3. Was a fidget to get the throttle out and put the whole thing back into the carburetor. Finally I managed that and wanted to do a test run. I then tried to start it by e-starter but he didn’t want to start it. Very briefly at the beginning it also sounded like the box was starting but then it didn’t start. Then I got it all rough again. Taken to see if the gas train might have jumped out again, but it still sat the same way I put it in. So everything was back to the carburetor and tried again, but again nothing was going on. This time it didn’t sound like it was going on at the beginning either. What could the problem be? Did I maybe use the gas train wrong from the beginning?