@alyoob I moved your post over to this existing thread: Content disappears when Premium Access ends
To clarify, it looks like your account is set up with the free service. Customized playlists (including your My Thumbs Up playlist) are only an option when upgrading to Pandora Premium.
I had our support team take a look at your account, and it appears you have been enabling free sessions of Pandora Premium by watching an ad.
This is what was allowing you to listen to your My Thumbs Up playlist.
When these free sessions of Pandora Premium end, your account reverts back to your regular service, and you no longer have access to playlists.
For a complete explanation of how Pandora Premium sessions work, check out the accepted solution to this thread.
Hope this helps!
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