Family member has a Galaxy Tab S (The SM-T700). It was rooted, but it got formatted (I think from TWRP). It looks like the bootloader also got formatted, and it seemingly has lost root access.
I can boot it manually into TWRP, but nothing else. I've tried to flash the stock ROM back, but TWRP keeps giving an error and refusing to flash.
Where am I best to go from here? I had a chat to the owner and it doesn't need to be rooted or anything, they'd just like it working again.