Can hear,but no one can hear me. - Motorola Mobility H710 Bluetooth Headset

Try a different Bluetooth (BT) headset. If the fault is resolved then it's a headset problem, if not it's your phone.

If it's your phone then go into the Bluetooth menu and delete your headset from the list of paired devices. Reboot your phone with a hard reset (pull the battery out for thirty seconds) and then re-pair your headset to the phone again. If the fault remains then you'll need to send your phone for repair or replace your phone.

A faulty BT headset is not a practical DIY repair, all you can really do is to ensure that the microphone pinhole isn't blocked by a bit of dirt. If this isn't the problem then the Motorola H710 is still a current model so might still be under manufacturer's warranty. If it isn't, then contact Motorola anyway as they may offer a goodwill replacement. If all else fails then it's not an especially expensive item to replace, but you might want to try a different manufacturer. I've used cheap Jabra units for eight years and I've only ever had three of them as they last so long. One got lost, and I upgraded the replacement when a smaller one was released which I still use daily in all weathers. Call quality and battery life are good and outstanding, respectively, and when the ear hook broke well outside of the warranty Jabra sent me another free of charge.

Good luck with fixing this, and I hope that my reply has been of some assistance to you. Please spare a moment to rate my answer.