Thanks for reaching out to the Community.
Have you tried running a clean reinstall across your devices? This would remove any corrupted leftover files that might be causing such issues. If the problem persists, what you could try is creating a new account and check if the same behavior comes up there as well. If it doesn't you can use the steps here to transfer you playlists.
Please keep in mind however that especially large playlists that approach the 1,000 songs mark could exhibit such behavior due to certain technical limitations. As an alternative we recommend splitting you playlist into smaller ones. We understand how this might be an inconvenience and constantly strive to improve the app and it's features, however we're unable to provide an exact timeframe for a fix.
Keep us posted how things work out. The Community is here for you if you have any questions.
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