Quickbooks web connector needs to be running to keep the sync up to date.

To Open Web Connector and Resync - You may need to restart the web connector if the computer has been shutdown or restarted.

Login to Quickbooks > File(Top Left) > Update Web Services

Check the box to the left of Payportal > click Updated Selected 

To Verify if the Web Connector is Running

The Web Connector icon shows up on the taskbar 

If you do not see the icon on the task bar, check the icons near the clock on the bottom right of the screen

You can also verify through the task manager (CRTL + ALT + DEL > Details Tab)