My Gmail app. for my LG G3 is not working,when I click on it it will ask me to add my email address and it say that this account already exists.I am able to enter Gmail through the browser but not through the Gmail app.I have downloaded this app.from Play Store uninstalled it and reinstalled it a few times trying to make it work,but it does not.Interestingly,the Gmail app.in my iPad is working fine.I am not positive but it started to happen when I updated my unlocked phone to Android 5.0.