Mk4 golf 1.6se not starting, cranks but won’t fire
 

So a couple weeks ago I drove to work and pulled up and left the ignition on and then the car wouldn’t start. Was driving fine before then, I’ve had an intermittent immobiliser problem where it would occasionally flash up but I’d switch it off and on and would be fine.
So far I’ve put a new battery in and also new battery in both my keys and no joy yet. First time I tried the starter motor cranked a few times then I heard a loud crrrrrkk sound when it should’ve started. The starter motor cranks but it’s not firing and revs don’t pick up at all. It definitely is getting fuel but it’s not even trying to start. Not had a chance to plug it in yet trying to organise it asap as I’m lost with it.