Unable to Update Supplier Name- Using API

Hi All,

We are on R12.2.10 and using API to update vendor name or some other fields and it is throwing error "Supplier processing failed. Supplier update failed. This Supplier Number already exists."

APPS.AP_VENDOR_PUB_PKG.UPDATE_VENDOR_PUBLIC(

P_API_VERSION => P_API_VERSION,

P_INIT_MSG_LIST => P_INIT_MSG_LIST,

P_COMMIT => P_COMMIT,

P_VALIDATION_LEVEL => P_VALIDATION_LEVEL,

X_RETURN_STATUS => X_RETURN_STATUS,

X_MSG_COUNT => X_MSG_COUNT,

X_MSG_DATA => X_MSG_DATA,

P_VENDOR_REC => L_VENDOR_REC,

P_VENDOR_ID => LX_VENDOR_ID

);

Please let me know if you have encountered this error or what might be the reason. Not sure if I'm passing any unwanted data.