Hi Vanessa. Which carrier are you with? It's usually set at default but some carriers can be adjust like here with Sasktel:

1. On your phone's keypad, dial (or tap):
   • * * 61 * 13065206245 * * number of seconds #
   • The number of seconds must one of these numbers: 5, 10, 15, 20, 25, or 30
   • For example: To set the ring time to 10 seconds, dial: **61*13065206245**10#
      
2. Press the Phone button (usually a green phone symbol at the bottom of the keypad).

• You may see a message saying the registration has succeeded and the ring time has been changed

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