Microphones convert mechanical movement (membrane) into a small voltage (inverse function of a speaker), so water likely went inside, and now the membrane does not vibrate any more and hence the microphone does not work. If it was salt water, it is likely corroded and will be damaged mechanically. If it was sweet water, you may be lucky and after it dries it may work again. You could try using a hair blower to dry it. If that does not help, there may be some small particles inside preventing the membrane from vibrating. Probably nothing much you can do about that.