I already owned MCC (since first launch..not so good memories) and pre-ordered Reach...same issue. I’ve got receipt of payment but can’t download and MS wants me to pay again. I too have done the reset and game management....none of this helps. It’s not you...another MCC launch I’m afraid.
I've personally brought this to Xbox/Microsoft support, the payment went through, you know on how if you buy something and it goes to your Xbox/Microsoft purchases, my purchase never went there so they didn't see the payment, then said "since we have no way to prove you bought it, we cant help you, sorry! The best thing for you to do is buy reach and ODST individually see if that helps." then THEY ENDED IT, of course, this is a VERY SMALL part of this otherwise this would've been the entire convo here, but it worked at least, spent $15 more to get something I already own... what a waste! spent $55, $40 for MCC bundle (SPOILER: bundle didn't work!) had to spend $15 more to get reach and ODST... sadly.