voice mail is not going to phone now even though it was working before

My boss has a new iPhone 5S and it was working OK for a while BUT now none of the voice messages people leave him make it to his phone. I always joke to him when he is not able to do something that it is probably the user BUT this time it is Apple. His messages do not show up anywhere even though we can leave them. I know for a fact it was set up as I helped him set it up and he has received message on it before. He says if Apple does not stop with these so called IOS improvement - they are going to lose a LOT of customers. I am starting to agree with him. Nothing was wrong with the last IOS and it looks like they have just made this one worst and it has a LOT of bugs!! Impossible to ever get in touch with anyone at Apple that has any authority to talk to you AND the people at the stores actually tell me that they do not have contact and that anything I tell them will NOT get forwarded to apple.

My boss keeps getting so mad that he said he plans to switch to another phone maker as Apple is really starting to upset him and the product does NOT work logically anymore.