Garmin Venu 3 Headphones

Hi. I just recently bought a Venu 3. For days now I'm trying to connect my headphones, but it just keeps saying that it's searching for them. I have JBL Tune 235nc TWS. I've tried turning off the bluetooth on my phone, deleting the headphones from my phone's paired BT devices list, I've kept them in "pairing mode" (in my case, it means just opening the charging case). The light on them keeps flashing blue, which means that they're in pairing mode, but my Venu 3 cannot find them.  

My old smartwatch (Samsung Galaxy Watch Active 2) connected to them instantly when I paired them for the first time. I've even un-paired the headphones and my old watch, turned the watch off, tried to pair while being at least 10 meters away from my phone, but still nothing. My watch software is up to date...