Please help me fix my phone

For days, Facebook Messenger would not stop crashing. Finally, I uninstalled it, and reinstalled it. Still it foes not work. Today, Skype did the same thing. I uninstalled it. And now, I can't reinstall it! I keep getting an error! I can live without Facebook Messenger, but not without Skype. Please tell me why my phone is being terrible, and please help me fix it. I have already tried clearing the cache/data on Google play store, and I have tried soft resetting. Please help!