As you confess to being a newbie I’ll give you some more detail.
What you have bought is a Universal Mobile Connector, UMC for short, not a charger. The charger that includes an inverter to change AC from your house and put DC into your battery is in your car.
The primary job of the UMC is to tell the car’s on board charger what type of supply is available so the cars charger will not draw too much power from the circuit. The UMC also monitors for things like if an earth circuit is installed and if higher resistance or low voltage is detected and throw an error code and or stop charging if anything is likely to cause a problem for the car or the circuit it’s plugged into.
In your case it probably detected higher than normal resistance and that’s why you got the error.
It’s all to stop the potential of fire, so it’s an important component, but it’s not the thing that does the charging.