Problem binding to interface , errno: 22 socket_bindtodevice: Invalid argument

I took these three steps in iSH.
- apk add nmap
- adduser iSH
- su iSH
Through these three steps, I can run nmap under ordinary permissions.
But I receive a new error:
Strange read error from 127.0.0.1 (1 - 'Operation not permitted')
Problem binding to interface , errno: 22
socket_bindtodevice: Invalid argument

Reproduce the three listed commands in iSH and run nmap as the ordinary user to confirm the permission and socket_bindtodevice errors. No source files or tests are named; done would mean identifying the cause and allowing this use case without the reported errors.

Written by the indexing model from the issue text.