Can't share my internet connection on iPad 3,3 iOS6

Hi everyone! I have a problem here with me.

I'm currently using an iPad 3,3 and I can't share my internet connection via the personal hotspot. I contacted my Carrier in Indonesia, which is 3 (Hutchison) and they said that the APN, user name and password for the tethering is the same for the one I'm connecting it to the network. But I can't enter the credentials in the tethering sections. Every time I entered it, it just disappears again when i go back.

Can anyone please help me or have any solutions to the problem? Sometimes I really need to do my work when there is no WiFi connection for my laptop in some places.

Thanks