You should absolutely fight an incorrect charge. You should also post about it in the public portal for your hoa so other members going after management about fixing it. We don’t get charged anything for using direct debit.

I’ll note the small possibility the outlet is wired wrong down the line as well. All the GFCIs in my house were intertwined circuit wise and would trip when another device would run down the line. Had to run an extra neutral line in one case. The random timing leads me to believe it could take OP that time to run something else on the circuit. Hoped it’s the lights. But you never know.

Why keep it for food?

Electric resistance is electric resistance. We don’t have heat pump ovens so you are not getting better than that. Using gas might be cheaper for a time but less efficient.