It's a 2018 model 4k, qled - 55PU something (can't recall exact model).

But it refuses to detect my headphones (Sennheiser Momentum 3). I can connect the remote, xbox controller etc.
The headphones work fine even on my 10 years old phone (some ancient Huawei).

I can leave it right next to TV, in pairing mode, let it scan and nothing.

Is this intentional/by design to save money or issue with Android TV/some config that limits bluetooth?