Unlock a Samsung S8 without the pin code

Not sure if this should be a thing, I have a Galaxy S8 and a SENA10 Bluetooth headset for my skid lid (motorbike helmet). Once paired I noticed if I turn the headset off the audio will stop obviously and looking at the phones screen it says swipe to unlock and input pass code. However if I leave the Bluetooth on my phone switched on then turn the headset back on being a trusted device it automatically re-syncs, then if I open the drop down menu from the phone’s locked home screen and press play on what I was listening to before turning off the headset the phone automatically becomes unlocked. Using Spotify to stream music not sure if that has anything to do with it? Wondering if anyone else here has similar Bluetooth headsets or headphones to see if they can do the same trick.

It’s probably a feature. Hidden somewhere in the lockscreen setting.

You can setup devices which if paired and in proximity to your device, are able to unlock your device.
Obviously this is not what you want.

You are on the money there, turned all that crap off when I set the phone up but it changes settings back to whatever samsung prefers apparently like the location sharing stuff turns back on every 24 hours.
Thanks