HELP ME HALO 3 odst code dissappeared

Games Halo: The Master Chief Collection
1

My code for halo 3 odst disappeared out of no where from my inbox someone please help me get a code back :confused:

2

https://www.halowaypoint.com/en-us/community/blog-posts/halo-the-master-chief-collection-thank-you-faq

You can try the forums provided in the link