By the way sorry about my double posts. I already check the server, i think this is not SI Bug.. from your explaination, i tried to check our servertoolconfig and look at "Falling_Blocks_Remover". Before this issue happend it was False, when i change it into True and happend this SI issue. I dont know this config related with planting seed or not. But i just tried to make it False again after read your replied and now we can plant seed again.
is it Falling Block Remover relate with all planted stuff? i mean like tree and seed..
Thank you for your support.