Garry's mod Server HELP?!?! (SB3_Server)

Hey guys I need help with my server,it’s up and running and works perfect, but the only one thing that doenst work is how the gamemode say’s sandbox, and whenever i try to change it to Spacebuild 3, it says Base gamemode. I need help with changing the name, because I want more people to join, and i want it to say Spacebuild 3: The new age instead of sandbox. HELP PLZ?!?!?!

changegamemode “[Gamemode]”

Now can you help me with this?!-Can-t-get-it-public!