Assuming that your goal is finding out where is your phone, there are multiple scenarios. I will cover two of them:
If you can find the mobile phone on "Your Devices" section (find it here), access it and press "More details" so that you can find the IP address. With the IP address one can find the location, bu using, for example, WHOIS IP Lookup Tool.
Error message: Installation failed due to: '-26'
Here is the solution which worked for me. Go to Project_Name → app → build.gradle file. And change string: targetSdkVersion 21 to targetSdkVersion 26. It will be a warning for version 26 but ignore it. Rebuild and re-run your project.
Hope this will help you like me.