Android ZTE - SD card unexpectedly removed.

A

AC Question

Signal Strength: -99dbm 7asu
Mobile Network State: disconnected.
IP address: unavailable

So my dad's phone keeps making a noise that's really bothering him, it's always a notification on how the SD card is unexpectedly removed. What am I to do? I don't know how to 'root' my phone or what that even means, I'm not tech savvy and just wanna help them out. What is wrong with this phone? Should I open the back and even bother touching anything? He doesn't use internet, very old school guy; just needs a phone that works and doesn't anger him. Do I need to call my service provider or is the phone itself fried in some way? Someone please help me with a diagnosis and ELI5 (explain like I'm 5)... please and thank you.