windows 10 – Microphone permanently disabled on MSI Prestige 15

A friend of mine has a very specific problem. She muted her laptop with the built-in mute button on her laptop’s keyboard which has since broken. She is now using an external keyboard that has no such button. Is there a way to unmute the microphone? I’m thinking it is either some mute functionality already built into Windows, in which case, how does she access that functionality without the keyboard? Or it is a hardware thing, in which case, is there any way to unmute it?