Why are calls ringing to multiple recipients at the same time?

When our primary number receives a call, multiple recipients' phones ring simultaneously even though we have that account set to ring in order. The idea is for calls to roll from one recipient to the next, but people keep answering calls that should be ringing only to the first recipient.

We have Incoming calls for that line set to ring in order and two total lines set to receive the calls. The first line should be the only one to ring, with the second one set to start after 6 rings (30 seconds), but yeah they both just start ringing at the same time.