Lookup fields not getting mapped

Hi , 

I am using IOrganizationService.InitializeFromRequest to clone a record (Phone call record) all other feilds are getting copied from the relationship mapping (Referenital relationship Phonecall -> Phonecall) but only the lookup and partylist feilds are not copied.  Can you help what i am doing wrong. 

Reference blogs i followed

https://balugajjala.wordpress.com/2017/06/01/clone-a-case-record/

https://temmyraharjo.wordpress.com/2022/05/08/dynamics-crm-populate-data-using-initializefrom-function/

Regards, 

Sanket Kumar