Great we are moving forwards
It measures correct at full
It measures correct at half
It measures correct at empty
The gauge and software and wiring are all correct
There's no shorts, open or high resistance
The gauge isn't directly connected to the sender
The level is calculated via a software algorithm to avoid the gauge jumping around up hills, down slopes
If it suddenly drops it's going to think there is a problem, until the ignition is switched off and on again
No doubt if you read the fuel level via the body computer with software it's going to be correct
Let's go back to the original symptoms, and try and understand what's going on
How long have you had the car, has it always been like this, and so on