You need to connect Jess to your Google My Business account before you can schedule GMB posts. Learn how to give Jess access to your GMB account.
From the Setup menu, choose Social/Local Sources.
Click +New Social/Local Source.
Type in your location name. This is the name of your business as it appears in your Google My Business listing.
Choose the Google account that you used to setup your Google My Business account.
Click Allow to grant Jess access to post to your Google My Business account.
Jess is now connected to your GMB account and you are ready to post and schedule posts using Jess.