Hello Atul,
Sorry for chiming in, but I'd like to make a small correction: table BUT021_FS will show you address-dependent communication data only. So both telephone numbers are address dependent. According to me the situation you're facing is the following:
1) BP n°320041 is an organization
2) This organization has an address with telephone number xxx
3) This organization has also a relationship to a contact person (to find the BP number of this contact person you can search table BUT000-PERSNUMBER = '12351')
4) Within this relationship, the same telephone number xxx is used.
What does that mean?
The same telephone number is used for different purposes (to contact both the organization, and the contact person within the organization). So you'd better ask one functional consultant within your company which one is better.
Regards,
Nicolas.