Cannot call a cancelled number from a voipo number

[wingsohot]

Can anyone tell me why, after cancelling an account, and the former customer has ported his number to a different provider, when you call the cancelled number from a voipo number you get a busy signal, but when called from an off network phone, it will ring through? Does this mean that a current customer cannot ever call a cancelled number from his current voipo number, even though the number was transferred out of voipo's network?

[VOIPoTim]

It may still be lingering in our system so our system routing it internally.

Open a ticket with the number and we can make sure it's fully removed.