Where to set ADR2-R3_USER value

Hi,

I hope my post is posted in the right place.

I've maintained telephone & mobile number in VAP1, where it will be reflected in Contact Person tab under Customer Master.

When i view table ADR2, the ADR2-R3_USER is blank,

my question is where do we set the ADR2-R3_USER to other values such as

Thank you for your valuable answers.

Regards,

Anthony