I am having precisely and exactly the same problem. I don’t know when it started (how helpful of me!), but I’ve been bitten by the same bug.
Here’s a little more info. Apologies if it’s unhelpful.
From the August calendar page (…/events/2017-08/), when I click on “September,” the linked page is …/events/2017-09/
And that’s the URL displayed in the navigation bar.
But, the August calendar is what shows up.
Unless I reload the page or navigate to …/events/2017-09/ manually.
This is to say, the problem seems to occur only when clicking on the link to September.
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PLEASE LEAVE FOR SUPPORT
Reporting the same issue as: https://theeventscalendar.com/support/forums/topic/month-navigation-not-working/
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PLEASE LEAVE FOR SUPPORT
Reporting the same issue as: https://theeventscalendar.com/support/forums/topic/month-navigation-not-working/