Harder than it should be I agree. Optus don't provide a clear statement of what people buy from the outset (something I'm amazed they get away with both legally and their customers seem happy to trust that they understood what was arranged despite no documentation supplied to the fact)
I suspect Optus have been pinged for potentially misleading a lot of customers over leasing plans. This has led to the end of leasing plans and in some instances people have simply cancelled the plans with no penalty.
Your case seems strange though. Its cheaper (on the monthly bill) to lease than pay for a phone. If you are getting a credit back every month then that sounds like you are on a lease plan? (The $10-$20 credit a month is the sole benefit of being on a lease plan)
That’s the thing as the bill said repayments clearly and they were $55.45 and then gave remaining payments left even though they credited it in the same bill but in 15 or more years I’ve always kept the phone and this is the first time I’ve had too give it back...
I think I need too get onto the ombudsman or get some legal advice cause it’s a joke...
So they said Payment $55 then Credit -$55 = $0 you paid? Sounds like you weren't paying off the phone this time. You should have got another $10 or so a month off the bill as well though. Seems like an awkward lease but not lease arrangement.
Anyway, if you're having no luck talking to Optus then I suggest you write a simple letter detailing the issue and how you want it resolved to the official complaints department.
Customer Relations Group PO Box 306 SALISBURY SOUTH SA 5106
You'll get an official response in a few weeks with an official complaint number etc. If not happy with the reply (or you get none) then you can submit that info to the TIO (ombudsman) who will then issue a please explain to Optus. The process takes a bit of time but you don't have to do much in the mean time.