I'm not sure what you have done but try these directs hope they help!
1) Hit the menu button on the AFTV remote and selected "Settings"
2) Went to "Profiles" and filled the following fields:
a) Changed Profile name to whatever I wanted
b) Entered MAC address from my Donation
c) Entered 13-character Serial number with one capital letter
d) Scroll down to "Device" (A regular mouse or keyboard might work -- no clue...)
e) Entered the 64-character SHA256 alphanumeric "Device ID" that I calculated using "Serial-MAC_Address-Donation#" (FTR, this is the same calculated Device ID I use in KODI.)
f) Clicked "Send Device ID"
4) Backed out to the main menu where it asks for the username and password
5) Hit the menu button on the AFTV remote again and this time selected "Keyboard" (This makes the Amazon keyboard pop up)
6) Quickly entered the Donation # and hit "Submit" then down-direction to "Password" and quickly entered Donation# again
7) Down-direction on AFTV remote to "OK" and the progress bar started making progress
8) Backed out to AFTV Settings and "Force Quit" STB Emulator Pro
9) Pulled power cord from AFTV then rebooted