Thank you for your post and welcome to the Bose Community.
I am sorry to hear that you are experiencing some issues with the microphone on your QC35 II's.
My first recommendation would be to reset the headphones.
This can be done by following these steps: Turn off the headphones and wait 30 seconds. Plug the headphones into a wall outlet using a USB charger, then wait 5 seconds. Unplug the USB cord from the headphones and wait 1 minute. Turn on the headphones.
Additionally, please visit btu.bose.com on your computer and ensure that the latest firmware version is installed.