Refuelling Runner

This has got to be the dumbest question on here but I still need to ask lol.

I got a Runner VX125 after owning a SR50, I went to refuel but under the petrol cap theres another flap, now question is.... do I shove the nozzle into the flap or do i just let the fuel drain in by itself?

 

Push the nozzle right in, through the flap, it´ll move as you insert

 

lol, i thought so i did that when i first fuled it up. cheers. its pretty tight in there though