Mobile version not working

http://www.perthcity.co.uk/calander

The mobile view in settings is set to agenda view by default, but it always seems to show poster-board – which doesn’t fit on the phone.

The user also can’t select from Categories or Tags, nor change the view to a different, more mobile friendly one.

Please note, this is when viewed through a phone (iPhone 5s and 5se) not when shrinking the browser window.

Any pointers?

https://wordpress.org/plugins/all-in-one-event-calendar/