Device name in Mac Terminal is a random person's iPhone?
Check your $PS environment variable for setting prompt:

echo $PS1


It might be

"\h:\W \u$ "


If so, your computer name is changed and you can edit it. If not, change it to that form by editing ~/.bash_profile

Also check that you are really on your Mac and not on an iPhone by this command:

uname -m


It should be x86_64 and not iPhone...