Why does my Z30 keep deleting my voicemails?

Hi everyone,

I hope you can help.

Whenever I get a new voicemail on my Z30 I call the number. I get the automated message, you have x new voicemails, but before going through the press 1 to listen to your messages I hear a number of key tones and "message deleted".

I initially thought it might be to do with the way I was holding my phone, or that my ear had some how pressed the buttons, but I've just done it all on speaker phone and my messages have been deleted without me touching the phone.

If it helps, I'm on t-mobile in the UK.

Thanks!

Have tried to contact T-Mobile? They might have a bug in their system...

Sorry for the late reply on this, turns out the speed dial for my answerphone had 2 extra characters that where promting the message to be opened and deleted immedialtly

I was able to change the voicemail number by going to the call screen, dragging down from the top to access the settings cog, then going to voicemail and reentering the proper number.