2011 rx 350 -How do i complete delete all phones and navigation

[SueAlphabet]

We bought this vehicle used and I thought I deleted all phoned from previous owner and all navigation but when i go to listen to a podcast when I click on aux it brings up the previous owners iphone and I dont know how to delete it.

What I want to do is completely get rid of all previous phone and data from previous owner. How do I reset everthing from scratch?

Thanks for your help.