My answering system plays my greeting to callers but will not record messages. Why?
Time of day is sent by your service provider each time you receive new Caller ID. This will reset your phone's internal clock. Some models have a CID Time Sync feature in the Menu, allowing the phone ignore the time set by your provider if it keeps resetting to the wrong hour.
Since the time is updated by your provider, you should contact the provider to see if it can be adjusted for your local time zone.