Welcome Myra_H,
Thank you for using Apple Support Communities. Based on your post, after updating your MacBook Pro your paired AirPods microphone isn't working as expected. We'll do our best to assist.
In case these are AirPods Pro, see: If your AirPods Pro make crackling or static sounds
Which would bring you to the following Repair Program: AirPods Pro Service Program for Sound Issues
With that provided, if you're using other AirPods models: Identify your AirPods
Then we'd still be sure to cover steps in: If the sound from your wireless headphones cuts out or is distorted
Should it persist, we'd recommend backing up and updating your iPhone to the latest version, if needed: Update your iPhone, iPad, or iPod touch
Pair the AirPods to your iPhone and put the AirPods back into the Charging Case. Leave them paired to your iPhone, connect the Charging Case to power, and close together with the iPhone for 30 minutes (Do not open the Charging Case during this time). In case they are out of date in firmware, this should update them. After that, play back some content (30 seconds or longer) to test the speaker using your iPhone, pair them with your Mac, and then try creating a Voice Memo on your Mac to test the issue further.
If it continues to occur, then reply back letting us know if you've had any issues creating Voice Memos on your iPhone with the AirPods.
We'll take it from there, cheers.