Can anyone shed some light on this?

I'm using a PAYG Orange Sim at the moment, my girlfriend is on Orange PAYM and we both have added each other as a magic number and Orange have confirmed by text to both our phones that it has been set up. But she's saying when she calls me, her minutes go down. I can't see anywhere in the terms and conditions or the Orange website that calling a PAYG magic number from PAYM takes your minutes away. It just says that it needs to be a number connected to the Orange UK network.

It shouldn't take the minutes. Calls to Magic numbers on Pay Monthly are free.

As a thought - the Orange billing system does not update in real-time. Her minutes going down may be from calling other numbers (or your number before you were a magic number) that were made over the last few days.