I am unable to set up my voicemail account.

When I go to set up my voicemail it asks for me to enter a pin. Once I have entered and re-entered a pin, I record my message and press "save". The loading signal then comes onto the screen with the words "Saving password..." but it never finishes saving. I have tried to do it just using the default setting, but the same thing happens. Is there just a problem with my phone or can I fix this?