Flatly only syncs data to OneDrive for Business which is an individualized version of SharePoint. Fortunately, OneDrive for Business files can be easily linked to group or company SharePoint storage by using Power Automate:
https://learn.microsoft.com/en-us/power-automate/add-manage-connections
OneDrive for Business to Shared SharePoint
Connecting OneDrive for Business to Team Resources
Written by Josh