Can you let us know if you've already tried to log out > restart your device > log back in? It's also a good idea to try clearing your cache to remove any old files that might be causing issues.
If that doesn't do it for you, could you let us your phone's Spotify version and, if possible, if you experience this on other mobile devices?
As for the screenshot, valid file types are: jpg, gif, pdf, png, zip, so we'd be grateful if you could try uploading an image in one of those. If you still have trouble you can also upload it on a 3rd party platform like for example Google drive and send us the link making sure it's not set to private.
We'd be on the lookout for your update!
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