I have done the update APN steps several times and restarted the phone. Also tried calling and texting. Call goes to voicemail. I rarely use the actual phone but going on trip and need to access. I did everything on the help section on solving this problem and am now down to submit a ticket. In iphone settings, my cellular says Error - an update is required to use cellular data on this phone. I have a iphone 5S with the latest IOS installed.
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