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In the meantime I'm a bit miffed by your problem but thank you for including some details. Personally I would do another factory reset. You'll obviously have to use the physical button method for your device to do this since you cannot complete the device set-up. While you're in that menu might as well wipe your cache partition as well. Did you choose to auto restore your apps for the last FR? It really shouldn't matter since it looks like you were not able to connect afterwards. I'm not sure if that will even be an option with the physical button method but if it is, decline. Doing these three things will give you the cleanest slate from which to begin all over.
There are some times issues with factory resets and they don't always take the first time. Sounds crazy but I've seen several times when items that should have been deleted turn back up or settings that shouldn't possibly be set still are because the FR didn't totally erase/reset everything.
Just a few quick questions;
When the device was working did you have any data savers, memory savers, anti-virus or malware apps? I recommend that you stay away from them if you did, and at least try the device for awhile before reinstalling anything like that. When crazy or odd things happen they are usually my first go to for why there's a problem and I'm usually correct, I didn't say always.
You mentioned that you were trying to add connections, did the connections you have still work?
This device was released in 2012, are you the original owner? In 2012 rooting devices seemed to be more popular than I've noticed these days, or maybe I'm just not looking in the right places, but is there any chance that the device was rooted? A rooted device changes all of the rules.
Unfortunately it will be hard to find support for an 8 year old device and honestly if factory resetting it again doesn't work there may not be much more advice to follow. Let's see if we can get can get you past the setup and see what happens from there.