why was a green robot on my samsung J36V screen erasing all of my files?

I took my phone out of jacket and on my screen a green android robot was opening and closing his/her mouth and underneath robot it said erasing. I could not do anything to phone it was frozen then shut down. Then came back on and prompted me as if it were a new phone that needed to be set up. I lost a lot of files that I thought were backed up to my Cloud. Since then ive noticed several apps that I never downloaded. com.ebay carrier, DT Ignite, CVS, RCP componets, android system web view, plus others. When I turn my phone on before i swipe it open 1 of the notifications box has TURN ON LOCK AND ERASE. Someone at verizon said "Its impossible for anyone to butt dial and erase an entire phone back to the set up prompt. Please help
Babs

Welcome to Android Central! Are you sure that eBay and CVS weren't already preinstalled as bloatware on the phone? It wouldn't be surprising. DT Ignite is a preinstalled app on Verizon phones to install other apps: What you need to know about DT Ignite, the hidden bloatware your carrier may have installed | Android Central. RCP components and Android System Webview are system components.

It's difficult to say for sure why your phone did a factory reset. People post about this happening from time to time, so it's possible that a catastrophic system glitch might lead to an unplanned factory reset.

Thank you for the quick reply. That is a great relief. I am not up to date on all these apps and what to keep what not to keep.
Again Thank you for your time.
Babs