I have Beoplay Ex Next-Gen Wireless Earbuds. They are blue-toothed paired to an iPhone 14 pro. But there is no option to select the earbuds as an audio source in the Control Center. What am I doing wrong?

I have Beoplay Ex Next-Gen Wireless Earbuds. They are blue-toothed paired to an iPhone 14 Pro. However, when I play audio on the phone, there is no option to select the earbuds as an audio source. (Only choice is the iPhone. I have successfuly paired an external speaker. I turned it off for this excercise.) I followed these instructions: "Open Control Center on your iPhone. Touch and hold the audio card in the upper-right corner of Control Center to control audio. Tap, then choose the device that you want from the list." The earbuds are not listed as a choice, but as I said, they show up in the blue tooth paired list in Settings. They do work with my older iPhone and iPad. How can I designate them as an audio source? Thank you for your help.