If your PDF magazine is taking unusually long to upload or the rendering process does not finish, there may be a temporary server issue happening.
You can check the current status of our servers here: https://status.yumpu.com
Please be patient and allow us some time to fix this problem (can take longer during night time or on weekends).
Furthermore you can retry by using an other browser.
If the problem still exists, you can get in touch with us under firstname.lastname@example.org