If you run a dual-write table map, you can encounter an issue called: "Missing data schema".

In this case, the entity list in D365 FO must be refreshed.

Standard procedure

1.	Sign in to D365 FO.
2.	Click Data management.
3.	First refresh the entity list.
	Click the Framework parameters tile.
4.	Click the Entity settings tab.
5.	Click Refresh entity list.
6.	Close the page.
7.	Now refresh the tables.
	On the Data management workspace, click the Dual-write tile.
8.	On the Action Pane, click Refresh.
9.	Run the task map again with the 'Initial sync' check box selected and the 'Master for initial sync' field set to 'Finance and Operations apps'.