I had this back in June/July.
As I understand it, a "E-Certificate" is issued by the system to the property hosting you for the value of the point you are redeeming. I assume this is an accounting thing for franchisees can "charge" corporate for reward nights. Normally when you cancel a points or points and money stay the certificate cancels automatically and points so back within two hours. Apparently sometimes the system gets "stuck" and the cert doesn't cancel and then you don't get your points back. I kicked off and customer services "loaned" me the points till they cancelled off several months later.