Why does Audiogon need my phone number to send private messages

I just don't send private messages anymore, so problem solved! They don't need my phone number and won't get it!

I had to authenticate on my iphone 13  by email and also by txt message which is bit much since my iphone 13 isn't my daily driver and has no service. It’s used as a strictly for porn, as a Roon remote, and to use the AIDJ ios app for (ROO-EXTEND Roon AIDJ Extension to curate great custom playlists and queues them in Roon using my voice). 

Anytime I log in they have to send me a text, how do I get my phone number off there list. Does that mean I can’t post anything without a text by.audiogon  I’m about done with Audiogon. I didn’t even bring up my payment method which they will never get. 

What I find odd is that AG does all these security-based requirements, which is good, but often deletes posts where people warn others about bad vendor / sellers.