RE: Account number XXX in company XXX is not mapped to account number XXX in company XXX.
Hi Navid,
In D365 the users are never "deleted" by design. When deleting a user in AAD or in the O365 admin center it will just sync and disable the user in the D365 orgs in that tenant.
A user name conflict occurs when you delete a user account, create a new user account with the same user name (either for the same user or another user with a similar name), and later try to restore the deleted account. To fix this, replace the active user account with the one that you are restoring. Or, assign a different user name to the account that you are restoring so that there aren't two accounts with the same user name."
For details about deleting and creating users, you can check links 1 and 2.
Delete users from environments - Power Platform | Microsoft Learn
[SOLVED] Creating a new user account that has the same name as a deleted user account - Office 365 (spiceworks.com)
Or you can check the field mapping. When performing a creation of a new record from an existing record, field mapping is involved, you can find the relationship based on the mapping list and select "Mapping", select "Generate Mapping" from the "More Actions" menu, this provides you with suggested field mappings for fields with names and datatypes. These will replace any existing mappings.
Information about field mapping can be found in link 3.
What is field mapping in Dynamics 365? - Gestisoft
Link 4 has similar questions and discussions as yours, you can check it out.
Customer account xxx in company xxx is not mapped to customer account xxx in company xxx while posting customer payments - Microsoft Dynamics AX Forum Community Forum
Best Regards,
Hana
