in simple words you can convert single into dual sim
take a phone G935F and root and read cert
open cert into notepad and make it dual ( manual already post in forum)
connect Same phone again and Put the cert which you edit for dual sim Just write it backup on Same phone
Done
you will get dual imei ( both imei will be same )
Enjoy Dual simcard Phone
Method is Tested and Working
Dont Ask for More