issue with Android device manager

[ZepTepi]

I got a second phone to use as a GPS tracker and I configured Android Device Manager on it as I did on my phone as well but when I left my new phone at home to test it and went to work it showed both phones at my location when I logged in two Android device manager. Is this a glitch or did I maybe do something wrong when I set it up? Secondary question, is there a better app for doing this than Android device manager?

thank you in advance for any help provided.

 

[lunatic59]

ADM tracks my devices individually. Are you sure you gave the proper permissions to the second phone to track it through wifi? (Or, do you have an account/sim card for that one, too?)