To sync / re-sync only one of your Groups...
OPTION 1
Click on Groups --> Search for the group you wish to resync. We searched for "Kids".
You will get two main sections of results.
Group 1: These are your integrated PastorsLine groups.
1. Click on the name of the group you wish to work with (gold box in image below).
2. Click on the Actions menu and choose Sync now from the dropdown menu.
Group 2: These are groups found in your external integration(s). They are not yet integrated with PastorsLine. Simply click on the purple Sync Group.
OPTION 2
Click on Groups --> Click on Integrations (gold box in image below).
Click on your integration and find your group according to the segments in the dropdown menu.
Click on the group and then choose Sync Now from the Actions menu (as in Option 1).
You can use the search (as in Option 1) if you have a long list in that segment.