What is the correct way to report a brand hijacking?

I see there are two ways to report a brand hijacking. I just tried to use the change a brand name in the help section and got nowhere quick with support. They said they can’t change a brand name. They could only change certain characters like capitalizations.

I also see there’s an option under brand registry, but I’m not sure what is the exact option to pick for someone who hijacked your listing changing the brand name only . We do have a trademark so I assume it’s under trademark, but I’m not sure which option to pick.

Thanks Annoyed seller