One radio works properly, the other can receive. I assume there are more than two by the question. Check and then rotate you batteries, mark on the working unit battery that it is GOOD. Transmit takes a great deal more power than receiving. Batteries, even un-used only last 18-24 months typically. If no joy, then check your programming but I think that is unlikely. It really sounds like a power/battery issue.
I can hear and transmit from one of them, when I press the PTT button, it comes through on the one walkie talkie, but I cannot get the other walkie talkie to do the same.