Usman-san, next time you have issues with NB, I would suggest you post in the correct thread please.
You must be registered for see images
There you should post your problem and what server you are on. ^_^
OT - Have you tried refreshing the page? If not and the issue is severe enough that it impairs your ability to utilize NB, then you should send a VM to one of the Admins, namely Zise.
There is also the option of clearing your cache and cookies.