Multipoint headphones keep an active link to two devices simultaneously — typically a laptop and a phone — so a call can interrupt music without re-pairing.
The rules for which device wins are set by the headphones, not by you. Many models give calls priority, some prefer the last device that played audio, and a few simply prefer whichever connected first.
That produces the classic complaint: you press play on the laptop and hear nothing, because the earbuds are still listening to a paused phone.
The reliable fix is to be explicit. Disconnect the device you are not using from its own Bluetooth menu rather than pausing the app.