Iconia One 8 B1 810 After factory reset, erase icon cycles continuously.

So the Iconia B1-810 is a tablet from 2014, nine years old now. They came with a small eMMC drive soldered to the motherboard for storage. eMMC drives have a fairly short life in terms of read/write cycles when compared to the more typical SSD used in laptops. There is a very good chance yours has either failed or is failing and can't write some of the data any longer. That's likely the root cause of the symptoms you are seeing. Unfortunately there is no easy fix, and certainly no cost effective fix. :(