Hey there, Bilsep2!
Thank you for reaching out to us here, and sorry to hear about the trouble you ran into. It sounds like the speaker is communicating well with the phone, but perhaps during the phone calls, it's not routing the call properly.
Can you check your call audio routing settings? This is located under your Settings>General>Accessibility>Tap Call Audio routing. Is it set to "Bluetooth headset"? Also, try toggling back and forth.
Can you test your speaker with a different mobile device?
Check back with us with an update when you get the chance.
Thank you again!
Mohsin - Community Support