POBOX number mandatory while filling up Profile details

While completing the form for initial application, PO Box number is a mandatory field. What should I do? I don’t have a PO Box number

[update] Never mind, it shows the form as complete even when I don’t enter PO Box.

What category are you applying in? I never faced this issue for EE

@avj : this is the profile completion after ITA in the contact section. Thought the field is shown as mandatory, the form is complete even if I leave it blank.