My phone works but the person I call can't hear me help!

To TS this issue, I recommend that you try a bluetooth. Call your friend using a bluetooth to see if you get the same results. Another way is to verify if your device have 2 mic. If it does, then when you call your friend, use the external speaker, this will activate the second mic allowing the party at the other side to hear you. If both mic don't work, it's a firmware issue. If the default mic don't work, but the second mic does work, then it's a hardware issue, meaning the the mic needs to be replace.

Check mic settings use Skype or other also it could be the cable is damaged to the mic