Good morning,
I have just bought a BV 7000.
Any time I make a phone call I hear the other person but unfortunately the other person cannot hear my voice.
Please let me know how I can solve this issue.
I do thank you in advance.
Regards

First try to clean flash the latest firmware. if that don't help you could buy a new microphone part on shopping platforms like aliexpress or exchange the hole device over your seller.