Finally after 2 weeks many phone calls problem was solved. I was asked to dial a number this then erased call barring which then allowed calls not to be forwarded to voicemails. I also found another way, I took SIM card out of Xperia and used in Samsung this allowed me to change settings for voicemail. SIM card then place back into Xperia bingo it worked. Settings for Xperia somehow had ceased to function correctly. Thanks for getting back to me.