728X90 banner problem!!!help me

in revenues&ads section it says about 728X90" This format randomly provides payperclick banners with additional remuneration." but when i put the code in my site it shows only one staic banner and never changes. 468X60 banner is also create same problem when i put the code from revenues&ads. but after put the short code from post section it works well. what is the problem in 728X90 banner! is there any short code for this banner that works!help me

my site: http://khulnatech.altervista.org

[Gianluca]

Your 728x90 banner seems to be placed correctly

whats wrong in it! can you help me ! please check it http://khulnatech.altervista.org

Your 728x90 banner seems to be placed correctly

whats wrong in it! can you help me ! please check it http://khulnatech.altervista.org