[Plugin: Events Calendar] Calendar does not work

Hello:

I need some help. I installed the calendar. I put the widget on a sidebar and also posted the calendar as a stand alone page. The page and the sidebar were populated. I went and added a post and published the post. Unfortunately, the post was not published and the calendar is like a picture. If I click a date nothing happens, there is no text in the date area.

I also noticed that on the sidebar calendar there were two arrows < and >, to advance the months but on the large calendar there were no nav arrows.

Please help me with this.

https://www.ads-software.com/extend/plugins/events-calendar/