If as you mentioned, you manually replicated the change (the column added) on the hub and the member database, and after that you updated the sync schema, it should have worked. The only option left for me is re-creating the sync group.
Database re-provisioning failed with the exception
I have an Azure sql db that I have a data sync with an on prem db. The sync was working and all was good. 1/31 we added a column to a table in the on prem db. I added the same column to my Azure sql db and refreshed the schema for the data sync. The new column appeared in the list of available columns, so I clicked it and hit save. The log message said "Schema information obtained successfully." The next time the sync was scheduled to happen the Azure sql was successful and the on prem db was successful, but the syncdata db has this error "Database re-provisioning failed with the exception "Invalid column name 'LegalHold'.Inner exception: SqlException ID: 0af6effa-f946-48f7-8f66-720c5f1de8a6, Error Code: -2146232060 - SqlError Number:207, Message: Invalid column name 'LegalHold'. For more information, provide tracing ID ‘3965e3ce-1026-4a53-9bf5-b04a836f3320’ to customer support." I un-selected the new column and everything synced successfully. But that isn't a solution. How do I fix this.