Fuel range indicator says I can drive 180 miles until empty. I drive half a mile and the indicator already says 165 miles left. What’s wrong?

My 09 passat, just started to give me what I think wrong fuel readings? I put some gas, indicator says I can drive for 180 miles til empty, 1 Mile later, it indicates 165 miles left? What's wrong? Is it using gas like crazy or is sending the wrong info?

My car has 101000 miles.
My car has an automatic transmission.

– Fuel range indicator says I can drive 180 miles until empty. I drive half a mile and the indicator already says 165 miles left. What’s wrong?