What model does it say in "About phone" (Settings-->System-->About phone-->Model number), @Arniekip?
More importantly though, are you able to register for My Xperia (Settings-->Lock screen & security-->Find my device-->Protection by my Xperia)(you need to register from your smartphone)?
If you are able to register for My Xperia, then it is genuine - My Xperia will automatically block any non-Sony mobile devices, based on the IMEI (serial number)... Including counterfeight smartphones.
