NFPS / Private Authentication Failed

IPTV Private Server (NFPS)
you can try this, it has worked for others....

c/p

This is what fixed my stalker client. You have to have to put in a 13'digit alphanumerical combo in serial number, 5 alphanumerical combo in deviceID and 5 alphanumerical combo in DeviceID2. Also in signature Imuse the last 6 numbers of donation number. Change one number on your MAC address and hit ok to save it. Then go and change your Mac on papiao.com.
Then restart KODI or clear cache and go back into KODI. This is what worked for me today.

I knew this is what it needed now to work, but I linked mine with a lesser amount of a alphanumerical combo a while back and it worked great until yesterday. So I am guessing this is what happened to you guys also.