A promotion in November 2017 to stay 2 nights and earn a free night I did but never received the certificate.
I was wondering the same thing. I have the promotion showing as an unused certificate but cannot find how to use the free night. Anyone have an answer?
Book a stay using points at a category 1-5 hotel. After you select the "points" rate, you'll get the booking page which looks like this.
Notice that the option to attach the unused e-certificate is already selected.
Complete the booking and the certificate will be applied to that stay.
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