So I got a message from "OptusTeam" saying this:
Hi, have you paid your Optus account?
Service restrictions may apply in 48hrs if your bill is not paid. You can pay online at https://secure.optus.com.au/paymybill?crn1+62311939565&amount=545.64, in the my Optus app app.optus.com.au/billing?tags=ARCLS or via your preferred payment option. If you've recently made a payment, or arranged a payment extension, please disregard. To contact us call 1509 from your Optus mobile.
Please help i have no idea if this is a scam or not, i bough a prepaid sim card and the data would not work if you didn't pay and this email claims i need to pay $545.64.
As @Paddylee , you should not click on links (unless you are 100% they are valid) .
As you have a prepaid service, you can never have an outstanding bill because prepaid services are always paid up front.
But having said that, it is a valid Optus link. Is that 62... account number maybe from another Optus account you have?