Help! Why does my Adv. Guestbook not post posts when written

I dont know what to do! When I went to post in my guestbook to make sure it posts, all I got when I pushed preview was the same page but it was blank... like I had to fill out the information all over again! The same thing happened when I hit Post. I am so lost! I dont want my users to go to the Guestbook and have to deal with this bs!! Please help me! I use this Guestbook because it came with the pagematic webhosting. Please help me and I know little about the codes and all so please when replying spell it all out lol! Thanks alot! Jessica

Does your host support the following?:

1. PHP 3x and up
2. MySQL database

I think this is all you need.