Marketplace Maps that were made before the nether update don't have the update fully. If you open the inventory, the blocks and items aren't there and if you somehow get it it's a dirt blocks with the words "update" on it. This is also for maps made before the buzzy bees update.
Thank you for your report!
We're actually already tracking this issue at MCPE-53693, so I will resolve and link this ticket as a duplicate.
That ticket has already been resolved as working as intended, which means this is not considered a bug and won't be fixed. Please do not leave a comment on the linked ticket.
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