Galaxy s20 plus volume

Using s20 plus and i cannot control the volume through my phone. Does anyone know what it is like this and how to fis this thing?
Thanks in advance

What is connected to that phone?

I have it paired with buzz plus and Q35

I just tried turing off the bluetooth and turning it on.
I have to connect to the headphone manually to be abled to control from phone.
When the headphone auto connects then i cant control the volume through the phone

Have you tried removing the device and then repairing?

I have the same problem with my S10+…I can’t control the volume from my phone (only the volume buttons on the headphones). I hope we can find a solution before I send these back. I wear over ear headphones all day (almost every day) while operating heavy equipment or while talking to customers during the day.