Answering a call right as it's forwarded to your message centre often is frustrating; in addition to being inconvenient, it can trigger a frustrating game of phone tag. The iPhone allows you to choose how long a call rings on your phone--between 5 to 30 seconds--before it is forwarded. Changing the ring amount on your iPhone provides ample time to catch those important calls.
Tap on the phone icon on the home screen to open the phone application. Tap on the "Keypad" option at the bottom of the screen to bring up the phone's number pad.
Key in "*#61#" and then tap the "Call" button. A message will appear about call forwarding. Write down the number that appears with the message. Tap the "Dismiss" button at the bottom to return to previous screen. For example, if the number that displays on the screen is "+3015551212," then write down the entire number, including the addition sign.
Key in the following sequence: "61", then the number, then "11," then how many seconds you desire the ringing to last, then "#," and then tap the "Call" button. For example, should you desire to allow the phone to ring for 30 seconds, you would key in "61+3015551212_11_30#" and then tap call. The length of the call ring can be set in 5 second increments from 5 to 30 seconds.
Tap the "Dismiss" button when you receive the message "Setting Activation Succeeded." The ring amount has been changed.