Setting not saving and can't register with passcode

I set up a course called Cloudland. It was copied from another course that was charged for. This class does not have a fee. When I uncheck "this is a paid course" and save it looks fine, then when I refresh, the box is checked again.
I set up registration with a passcode, when I try to register, it says "successful, start learning" then goes back to the screen to enter passcode.
If I disable the Marketpress plugin, then it works.
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