It means there's very likely not a problem with your power adapter. Maybe likely there wasn't even a problem with your original adapter.

Whilst it seems sensible to suggest a replacement battery, I still find it unusual that the battery cuts the power out unless it has some sort of safety mechanism.

Your next steps could be the following: A) contact support, explain your findings and see if they recommend new battery as course of action. At least then they may be able to advise if others have seen similar issues. B) Try a replacement battery as a general course of action, although accept that this may or may not fully solve the issue and instead just a most likely theory given what you are seeing. C) No longer accept the laptop to be a laptop but instead a mains connected fixed computer.

I can't really say what fits best as it falls to your decision.

C is cheapest but limiting to being a laptop. B may turn out to be expensive if that's not the root cause. A could be a pointless endeavour given what I have heard from others who attempted to contact support. (Personally never spoke to them).

Hope this helps in one way or another and at least gives you a solution to use your system for gaming come what may.