Controversial Topics Several months ago, I added a private sub-forum to allow members to discuss these topics without fear of infractions or banning. It's opt-in, opt-out. Corey Click Here
You cannot modify a reservation online, you need to contact MS. The online sytem is not set up to allow any modifications to an already existing reservation. The only way to change a reservation online is to cancel the whole thing and then make a new reservation subject to availability at the time you try to make the new reservation. You can as suggested above separately reserve the extra day and then contact MS to merge the two reservations.
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