Make sure all computers in the household are completely logged out.
Give it a minute and try to log in.
If more than 1 real life person wants to play from the same IP address you will need to apply for an IP Exemption.
Info found here:
https://www.project1999.com/forums/a...ement.php?f=25
Post here:
https://www.project1999.com/forums/f...splay.php?f=25