cook top kitchenaid

I have Kitchen Aid cook top with double built in Owen. For 8 months it worked fine, three weeks ago i clean the cook top with damp cloth took out the knobs clean them & put them back, to my surprise only two right burner work,two at the left And one in the center do not work ! i can not even turn the knobs,it seems as some thing locked them.

i am very frustrated can some one help me please ,thank you so much. Tsayed