I have tried the below steps. I have uninstalled, reinstalled, deleted the folder, and downloaded the worlds again from the marketplace. I followed what I found on the forums but nothing is working. Please help! I can create a new world but none that I have purchased from the marketplace.
Uninstall Minecraft
Delete the com.mojang folder (Device storage > games > com.mojang)
Reinstall Minecraft
Thank you for your report!
However, this issue has been closed as a Duplicate of MCPE-51520.
From the @MojangStatus account
Bedrock: Some players may be having issues loading/playing Marketplace content. We are investigating the issue & will update to let you know when it is fixed. - HZ
https://twitter.com/MojangStatus/status/1169406413992550400
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