206 1.6 petrol manual not working problem

First of all, hello guys. There was no problem with my car 2 days ago. Yesterday morning, I got in my car, pressed the starter, it didn't work. The starter motor is running. There is no problem with the battery. The electrician looked at the fuses and said there is no problem. I don't remember if there was a noise from the fuel pump. When he hit the car, it worked, so the vehicle takes the gasoline to the engine. But I guess it doesn't fire when standing normally. We thought the problem might be the spark plugs, but this morning when I started the starter it worked, then I went to the gas station to get gas. In the previous topics, they said that it could be caused by the immobilizer, but my problem is most likely not caused by it. Why do you think it might be? Thanks in advance.

I don't hear the squeaking sound that should come from the gas pump, friends, I went and looked.

Lift the seat of the rear seat and remove the black cover. Tap it a little with the back of a screwdriver so that it doesn't break. Listen to the sound, is there any change? Sometimes it clogs somehow, but if it's faulty, it needs to be replaced.