Gmail — password change

Address:

Jalandhar, Punjab

A person name ajay who is my friend has changed my password . i know how he do it. He has taken my phone for some purpose and then he try to log my id in his phone but he don't knew the password and then he click on forget password after that a code is sent to my phone from where he get the code type the code in his phone . and changed my password . My email id is [protected]@gmail.com please help me caught him...please and he do this for getting asscess to my account of clash of clan connected with google + .