Hi @hamzanadeem. Is your phone unlocked (SIM free) and from the UK?
Thanks for confirming. Are you currently based in Italy too, @hamzanadeem?
@hamzanadeem: As your phone was intended for use in Italy then this may be the reason why you are unable to enroll in the Beta, as it was not officially rolled out in that region. If you head to Settings > About Phone > Software Information > Service Provider Software Version, does it say BTU here?