My phone Samsung galaxy was factory reset

[AC Question]

My phone was normal. I took after some time..it showed welcome select language. I selected the language and it brought me to another page. A pop up appeared which read "an unauthorised factory reset was done to your device " something like this.
And it opened normal view of my phone with nothing...all got erased
.only the inbuilt apps were set

 

[Tim1954]

That's what factory reset does. Resets the device to how it was when you unboxed it.