Today I went to my local optus store and switched to a postpaid plan,
they gave me the sim card.
i went to go and activate it but it shows a error saying that it isn't vaild.
I'm not sure if they went and activated there or not.
Put the SIM card into your phone and see if you can use the phone. If not a visit back to yiur local Optus store.
I think if you are missing some details it may be easier to get it activated on online chat
If you require any further details, don't hesitate to send us a private message