Where is the fuel reset button on citroen nemo van 12 plate please? If there is one you can access of course.

check for a faulty fuel pressure regulator

With ignition key off .. Hold right button down (2 buttons within the instrument cluster) Turn on ignition.. but not engine.. Watch for countdown till zero.. Release button.. All done....!

With ignition key off .. Hold right button down (2 buttons within the instrument cluster) Turn on ignition.. but not engine.. Watch for countdown till zero.. Release button.. All done.

The most likely being a faulty EGR. take it to someone who can hook it to a diagnostics computer and find out what exactly is going on

Reset oil light after service... that is very important. And don't skip the oil change either.

1-turn on the ignition key,
2-press the gas pedal and hold it,
3-press the brake pedal 7 times without relesing the gas pedal,
4-keep pressing the gas pedal for 60sec.
5-Release the gas pedal and turn of the ignition key,
6- Wait for 60sec.
Then turn on the ignition key and start the engine. Check if the service/oil change light turned off.
That's it. Worked on my 2011 nemo van.

try this:

Sounds like a vapor lock. disconnect a hose on the filler neck if you can or try to relieve pressure in the tank.