Hi,
Thanks a lot for bringing this issue up. I assume you are referring to Udemy? They currently seem to have technical problems. If they don’t get fixed soon and if you don’t want to wait, I’d suggest to migrate the GameDev.tv courses you purchased on Udemy to our website. For free, of course.
https://www.gamedev.tv/p/udemy-migrator
Did this help? 
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