I programmed the NRF9160 Feather via NRF Connect and JTAG (using Erase and Write). This erased the boot loader and broke the USB update process. I downloaded v2 of the boot loader and flashed using nrfjprog – but it would not bootload. I tried v1 of the boot loader, and it almost works – when I upload via newtmgr, it stops at 96% and gives me Error: 3. What am I doing wrong?