So you have 2 services that share data together? If so, you'll need to contact Optus and request they be put on seperate accounts, that's the only way. I'd speak to them on live chat - http://yesopt.us/chat2us
You should find a spot in MYACCOUNT on the other phone number to CHANGE OWNERSHIP.
Check your bill to see why $45 was charged (was that $45 extra or $5 extra on a $40 plan?)
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