[japanjapan]

Please read the following sentence, this may help you resolve your puzzle.

I know you are a kind person, but you are wrong this time.

well, if the sentence is like this:

I knew you were a kind person, but you are wrong this time.

or

I have known you are a kind person, but you are wrong this time.

these two sentences are correct grammatically, but if the speaker thinks it is not necessary to emphasize the meaning of "already", he can say" I know..."

do you understand? now read you sentence again, do you still think it sounds odd?

I hope this is helpful.