Data like username transferred via a HCM extract via VDS to the Identity Center often have language specific characters replaced with hash character instead
The LDAP connection from the HCM system is not configured to use unicode
HCM, VDS, unicode
In the HCM system the connection to the VDS will be defined in transaction LDAP. Here you will see the LDAP connector maintained. This uses a connection defined in transaction SM59. This needs to be configured to use Unicode in the connection
Go to the LDAP RFC connection in transaction SM59.
In this definition choose the "MDMP & Unicode" tab and under "Communication Type with Target System" choose "Unicode".