Stout Google Calendar disappeared

Hi, I have the Google Calendar plugin and have used it successfully on the home page and calendar page: http://highbridge.org/ and http://highbridge.org/high-bridge-calendar/ . This morning I got an email telling me the calendar is not appearing. It has disappeared on both pages. No one has changed the code. Can you tell me how to go about troubleshooting this type of problem? Updates were made to the Google calendar itself and the calendars were visible after the updates were done (I have a printout of each). I’m wondering if there’s some conflict with the ‘custom’ feature in the new version of WordPress where you can see the sidebars and edits them in that mode. Any advice would be greatly appreciated.

https://wordpress.org/plugins/stout-google-calendar/