I have just joined smarty and kept my old number so why are my iMessage not working

[KatHart]

Need to get my old number working 

[MSF]

@KatHart  This has been dealt with many times on the forum. It's because your phone has 'remembered' the original number on the sim. You can do a network reset and also logging out of FaceTime and iMessage and then logging back in may help.