My Motorola FV200 won’t transmit

Hi everyone!
So I have this old FV200 and for some reason one of the walkie-talkie is not working. Basically it’s receiving all the time but it won’t transmit anything out, so the whole time you can hear the white noise coming from it. Also, and I don’t know if it’s for the same reason, some of the buttons don’t seem to respond, so I can’t change the channel or any other thing apart from turning it on and off. Any ideas of what could be happening?
Thanks