For some POS systems once you update/add items in your POS System the POS sends ToGo an updated menu file. Check to see if this updated file has been received by ToGo.
Login to Order Cloud
Select Manage Stores
Select the Location
Select the Admin tab
In the POS Configuration section if the POS sends a menu (raw data) file to OrderCloud for the sync you will see a date/time stamp under Raw Menu Data
Make sure this has been updated with at least the last date you made changes to the menu on your POS.
This Raw Menu Data file must be updated with the changes for the sync to get the changes and apply them. If there is no date/time entry then your POS does not send us data, we pull data directly.