Hello! I'm Jen, and I'd be happy to help you out with this issue.
I'm sorry to hear you're experiencing this issue. Can you please check if you have Speech Recognition enabled in Windows settings? Sometimes, a bug or glitch disables the setting automatically. To verify, go to Settings > click Accessibility > click Speech > make sure to toggle "Windows Speech Recognition" button to turn it on.
If the problem persists, please check if the application for which you need the speech recognition for has microphone access. Go to Settings > Privacy & security > Microphone > Enable "Microphone access" and "Let your apps access the microphone". Let me know if this works. Thank you.
I hope this information helps. If you have any questions, please let me know and I'll be glad to assist you further.
Best Regards!
Jen :)