Phone Country Code Duplication Check is not working for agency candidates.
SAP SuccessFactors Recruiting Management
The system is working as designed and this is expected behavior. When Agency ownership settings are enabled, there will not be a phone country code duplicate check. Duplicate candidate check happens only on e-mail Address but not on Phone Country Code when Agency ownership settings are enabled. If you want to use Phone country code duplicate candidate check, you must disable Agency ownership settings. If you would like to change or improve this system behavior I suggest you submit an enhancement request to the product management team which will be reviewed and voted on and could be included in the next release of the product.
2090228 - How to Submit Enhancement Requests for SAP SuccessFactors Products
Agency Candidate, Phone Country Code, Duplication Check, Agency ownership, settings, e-mail, verification , KBA , LOD-SF-RCM-CAN , General Candidate Issues (not Offers, not Profiles) , Problem