How to re-map a user which is already mapped and marked for syncing in ADSync tool ?

Question : How to fix synchronizing issues for an AD User that was mapped earlier with a user on Target DC by re-mapping it?
Answer: Steps given below can be followed to handle the scenario where a user was mapped earlier in the ADSync tool but lost the capability of syncing attributes/passwords etc :

Step 1 ( Clearing DesktopProfile Value ) : Remove the value of "desktopProfile" attribute of concerned AD user from both in Cloud and Client AD side by clicking on Clear and then OK buttons. See the below screenshot for more clarity.

Step 2 ( Removing User Membership from OU_Sync security group and Remapping ) : Second step is to remove the user from mapping by following the below steps:
i) Remove the membership of the concerned AD user from the OU_Sync security group created by HCDirSync utility.
ii) Open HCDirectory Sync tool and navigate to Cloud AD Settings tab (See below screenshot for clarity).

iii) Now by clicking the Mapping link a new window will appear, in the search filter locate the concerned user in Local AD and then specifying the userPrincipalName under Account Name in CLoud AD column and click on Save Mapping button. A user links with an existing cloud user making use of the userPrincipalName attribute. Therefore, if the UPN suffix on cloud is different than that on the Client DC, then you will need to explicitly specify the Account Name while mapping it. See below screenshot for clarity.

If problem still persists then do not hesitate to send an email to to get further help regarding it.