Please try to reload https://feedly.com/ in case this is due to a networking or caching issue.
In some cases, some browser extensions can interfere with the loading of Feedly. If you have some browser extensions installed, try to load Feedly in an incognito window and see if that resolves the issue. If it does, you can try to disable extensions one by one to determine where the conflict is.
Finally, this could be caused by a bug in Feedly. If this is the case, please send an email to [email protected] and we will be happy to help.