Yea, I tried everything, and on my every device (iOS, iPadOS, Android 10) there are no arrows that can reverse the order like before, so I suppose it was probably removed at some point, because I just have this check symbol.
Thank you for keeping in contact and for the screenshot you sent.
We tried to replicate this issue, but the sorting options are still showing an arrow up and arrow down when sorting the tracks of a playlist (excluding Custom order).
To keep investigating your case, would you mind confirming if you perform the clean reinstall as suggested previously by @Eni?
If so and the issue persists, it would be great if you could have someone log in with their account on your device - such as a friend or a family member, to see if the issue persists in other accounts. This will help us understand if it could be account-related or not.
Lastly, could you share with us the link or URI of one of the playlists that is having the sorting issue? This will give us a better look at the issue.
We'll be on the lookout.
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this is same for me. spotify not only removed the option to reverse sort by date added, but it has unsorted my previously reverse date added sorted playlists and theres no longer the arrow up and arrow down options.