You have the NickServ setting of “protection” on your nickname. When you log onto the chat server, and there is some time delay between NickServ recieving your password your time limit expires and NickServ “protects” your nickname. This is because NickServ has not yet recieved your authorization so it does not know you are you. It then changes your nickname forcefully because it is protected. You may want to drop the “protection” option and opt for “security” in it’s place. You can still take your nickname from someone that is using it when you logon and find them doing so. Or you can endure NickServ’s forcefullness now and then when things are running a bit behind.