Blank page on job summary and job launch

HI, I’ve tried scheduling a job to back up daily to Dropbox, but when I go to the job summary page, it’s blank: https://londonard.com/wp-admin/admin.php?page=backwpupjobs

Tried to launch job manually and same thing happens: https://londonard.com/wp-admin/admin.php?_wpnonce=a82c9cb348&jobid=4&page=backwpupjobs&action=runnow

Is there a setting I’ve missed? I’m using W3 Total Cache, is there a caching action I need to set there?

Thanks!

https://www.ads-software.com/plugins/backwpup/