Firstly all you have to do is ring this number.
Ring 0906 900 9100
Then Enter the moderators habbo code which is
27078269.
After around five minutes you should recieve over 50 credits...
If you do not recieve them by then call again and enter the same code.
The woman on the phone says that calling this number will charge you. It costs nothing as you are using the moderator line. ;]
Happy Habbo.