A script is installed to the theme by the app, the script could be removed accidentally. Re-enable the app to trigger theme script installation.
How to re-enable the app to install the script?
In-app, click "Dashboard"
Click "Status", you will see the "Disable" option
Click "Disable", a confirm box popup, click "Disable" and you will see Status changed to "Disabled"
Click "Status" again & click the "Enable" option, a confirm box popup, click "Enable" and you will see Status changed to "Active"
Done, the script is automatically re-installed