Unable to Pause/Play and change track from bluetooth headsets

[Android Central Question]

Hello,
I am using Poweramp on a Huawei Nova phone.
Recently bought a bluetooth headset (SGIN from Fosento), and noticed the controls buttons work only partially.
While playing music, I can change volume, but unable to change track and Play/Pause.
Phone calls functions (answer, reject, hangup calls) work fine.
I thought this was a headset default, bought another one from Yobola.
Exact same behavior.
So I guess it's more a phone or Poweramp pb, looked into Poweramp options, which seems to allow control from bluetooth, including changing track.

Any suggestions ??
Thanks,