Astra 2G signal problem in Germany

Hi,
i am using SelfSat H30D Satellite.i am trying to catch the Astra 2G. i have good signal,when i scan then i got all the transponder but i got not channel at all.
i thought this could be the dish size issue. SelfSat H30D is 56 cm.

i am living in 82433 Bad kohlgrub, Germany.