Heads up guys: if you purchased Halo 5 Guardians Limited Edition ($99.99 USD) or the Collectors Edition ($249.99 USD) the code for the game comes with the Warzone REQ packs with the game code. When you installed Halo 5 to your Xbox One using this code you also installed the Warzone REQ pack ($24.99 USD) as well. There will not be an "Add On" in your manage games section for the Warzone REQ pack. If you purchase another you will run into the issue I have which is two licenses on the same account. Buying a second Warzone REQ pack will not give you additional packs as of right now. I am unsure if after all 14 packs are delivered if you can get another Warzone REQ pack or not but as it currently stands I am unable to when I talked to Microsoft Support and I'm working on getting a refund for the second pack that I bought (thinking I could get more packs).
When you load up Halo 5 Guardians and open your menu, go to the Requisitions tab and choose Open Packs. There should be two packs for you to open. If you have opened these packs then these are your first two packs from your Warzone REQ pack (You get 14 total, 2 every week for 7 weeks.) You will have another two packs next week whenever the game is flagged for the weekly reset (I'm assuming this is from the launch date, so Tuesday's you'll get another two packs.) If you did not receive your 2 packs then I'm currently unsure of how to get those for you if you are using the Limited edition of the game.
For those of you who have purchased the standard edition of the game, have purchased and redeemed your Warzone REQ pack and have not received your packs please try the following:
1. Confirm that you have the add-on installed under Halo 5 Guardians -> manage games and confirm that it is installed.
1.2 If it is not installed, please install it and confirm that you get the confirmation "add-on installed"
2. If you see the add-on and it's listed as "Installing 99%" (Or any other percent and it's stuck) press the menu button, cancel the install and try to install again.
2.2 If it gets stuck again then you need to power cycle your Xbox One. Confirm exiting Halo 5 Guardians on your console, press and hold the power button on your Xbox One for 10 seconds (You should receive a sound to confirm it shut off). When you start the Xbox One up again you should see the green Xbox One screen to confirm the power cycle. After this you will see one of two things A: The Warzone REQ pack will not have been installed, and you can install it (this should go through and fully install) then you can get your two packs or B: The Warzone REQ pack has installed and you will have your packs.
2.3 After confirming the installation of the Warzone REQ pack load up Halo 5 Guardians and go to the Requisitions menu, select open packs and your two packs should be there.
These are the steps that I have used to fix add-on's in the past as well as making sure it fully installed so it could be added to my account. If you manage to install the Warzone REQ pack and not receive your packs then you may be having a different issue and I would recommend contacting 343 Industries to see if they can check the status on this.
PLEASE NOTE: I am not an official support member for either 343 Industries or Microsoft, I am just a consumer of a wonderful product. This information may help others and I would like to be able to help as many people as I can with this information. If this information helped you at all, I'm very glad to have been helpful. If it has not, I'm sorry that it did not help you. This is what I've done and consulted from other people to fix my problems as well as make sure I'm getting the best experience possible.