Bluetooth accessories not playing audio although paired with my iPhone 14

if you have not made the phone forget the headset

and then put it back into pairing mode

and pair it back to see if that resolves it

if it does not then if it was me then I would try to pair it with something else to verify the speaker/headset is not defect

I had that issue with some bluetooth external speaker the other day.

Have you paired them with something else? I have had this problem for a long time when my Sony headphones are paired to my Apple TV and I try to pair them with my iPad instead. They show up as connected on the iPad but no sound is playing. Same thing happens the other way around; if they are connected to the iPad and playing music I can seemingly connect them to the Apple TV (Status connected) but I can't use them. It seems that many have reported problems like these for years, but Apple is busy with core functionality like memojis and stickers.