Disappearing petrol

I went there to pour petrol for 300 this morning, my tank was empty so It was 2 bars up OK dropped my daughter off at day care that's like 8 minutes drive, then I went back home switched the car off to open the gate start the car boom my tank is empty light is on to my surprise 😲 switch it on and off again maybe the car is crazy doooo petrol empty I went back to the garage spoke to the guy he called his manager says there is nothing he can do it's only 13 liters... I'm like 13 liters can't be finished in just a few minutes drive no matter how expensive petrol is or how my tank was empty to move from 2 bars to light on in just 30 minutes and my car just came back from service in January