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It is a bad idea to have a board of directors made up of an even number (2,4,6, etc.) of people, because deadlocks can occur. But in this case, it is unlikely that he legally conviened a directors meeting without telling you; and if he did, it is also unlikely that a quorum was present. Therefore he could not legally change your title.
It appears that he is fraudulently changing the registration with the state. Send a letter to the state agency, copy to your "partner", notifying them that you are resigning as the CFO, that the change in resistration purporting to change your title to secretary was not authorized, and that you henceforth are not connected with the corporation in any way.
I take it that you have no desire to be compensated for your shares.