Delete the data from my stolen IPhone
Hi. My IPhone was stolen a week ago. Yesterday I got a message from Apple that said that my phone was found. Then I got a message that someone signed up in my ICloud account so I decided to change my password and pressed the button that said to log out from all devices (it was very stupid I know). What can I do now? Now I don't have that device in my ICloud. I want to delete all the data from the phone. How can I do it?
Thank you
iPhone 6s Plus