When I try to access two of my Minecraft mashup packs (Pirates of the Caribbean and Star Wars), they are stuck downloading and have been like this for months.

I'm on the pocket edition, but they are still inaccessible through my Xbox. I can still access the skins, I just cannot create the worlds, even though I used to be able to. I could possibly delete and reinstall Minecraft from my phone, but the last time I did this, all of my worlds were consequently deleted, and there is a world on there which I could not afford to lose.