Different Tax Refund
It depends on what tax refund you are referring to. If you paid GST with your rent, then it is refunded with quarter GST Refund that you would get if you filed your tax last year. If you have not received carbon credit refund, then you may not have file last year's tax return so the government has not basis to give you refund.
Also if you paid your rent privately to a private landlord, there is no GST.