I believe its in account settings. I did it a while ago so I do not remember all the steps. It should be easy and Listia should have steps for you to get it but try account setting first
If you go to your profile, on the left hand side of the screen under you account picture there is a row of different circles. You have verified your FB account. What you have left to verify is user account,phone number account,ect. After you verify your user account you will get a lot more people to bid on this. I hoped that helped.
I couldn't do it through the app so I had to go to the web I verified my phone number I haven't put my bank account number in there yet cause I haven't bought anything but eventually I will I've never not sent any of my packages out basically I try to trust the people that I send my package is too they want to screw me over I'll learn let's just hope it doesn't come to that