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Personally, I don't believe there's anything generally wrong on your end of the problem Ms. Starry. My assumption is the creators of said pack hasn't provided the item itself or an item's texture in the download as I've witnessed this happening with various item packs. It could be a glitch on their end or it could be they got lazy and decided not to do or texture a particular item in the long run. I could be wrong but again, I don't believe there's nothing wrong that you did but instead the problem originates from the creators.