"HTTP status client error (400 bad request) for url ()"


I get this error every time I open, close or sync the app. I haven’t been able to sync my cards to the web or mobile app since I’ve started seeing the error. I don’t know what this means and how I can fix it. Any help would be greatly appreciated. Thanks!

To help with the troubleshooting, you should work through the standard list of suggestions, then report your findings:
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When problems occur - Frequently Asked Questions (ankiweb.net)
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Thanks
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I did and I couldn’t get it to work.