i have an iphone 4s on orange (uk) until about a week abgo was working fine. until i was asked why i wasn't replying to my friends messages i didnt realise i was recieving voicemails & missed a weeks worth. i get the banner to say i have a misssed call but not notification of a voicemail being left. i checked my settings when ringnig voicemail & all alerts are turned on. i used to get a text message to say i have a new voicemail now nothing. any ideas what i can do next?