2020 Oil Change (2.0l T engine) - trouble with drain plug

[Pablo20]

I tried to change the oil in my 2020 NOX. I was unable to remove the oil drain plug. I'm certain I had the right place (back side of oil pan, centered, near bottom). It was 15mm hex nut and resisted all attempts at turning it.

The dealer did the last change. I have a hard time believing they tightened the plug so tight - maybe they used an alternative method to remove the oil.

Any hints? Am I missing something?

Thanks in advance ...