Hi @Amoughvgowda ,
Based on this post : AD Account Provisioning Error - Identity Security Cloud (ISC) / ISC Discussion and Questions - SailPoint Developer Community
It seems like that only the accountID on the source (distingushedName attribute support the username generator) but not the sAMAccountName.
For sAMAccountName you can try :
- Account Profile Attribute Generator (from Template) | SailPoint Developer Community
- Extract the samAccountName from distinsguhedName