Free will can't exist under an omniscient entity

If you believe in an omniscient god, then you by definition can't have free will. Here is my argument:
Your omniscient god (hereafter og) knows all (by definition).
Your og knows how you are going to die and when.
Your og knows what you were doing 1 millisecond before you died.
Your og knows what you were doing 1 year before you died.
And so on until we get to creation. If all was known prior to your
existence, then you actually had no free will, it only appeared that way to you.
Q.E.D.