307 Fuel Gauge Problem

Guys, today I completed my car's tank, so I filled it until I pumped it. When I got on my car and started it, 4/3 of the tank was showing full. Another event that caught my attention in the last few years is that the fuel is not lit until the diesel needle goes down to 0, so that lamp is lit too late. I would be glad if you show a solution .. Thanks in advance.

If your problem is caused by the float and you remove it and clean the electronic card where the float's bar is working, your probability problem will be solved.

Thanks efe, it is worth trying. I don't know if the cover of the float and its gasket had changed before, it was a malfunction that occurred that day.

Could it be good to look at it?