Hi @Goh_Ser_Ming and sorry for the hassle with this.
The Smartphone controls were transformed to iPhone controls because our previous editor version (which uses the BMML file format) didn't have the Smartphone control created at the time.
Are you moving your project to another Mockups 3 product by any chance?
If that is the case, you can directly open the BMPR file there, without having to export it to another format.
Also, if you need to move mockups from one project to another, you can directly drag them there.
Hope this helps! We'll be here if you need anything else.