You can also give feedback to the NDIS Commission: They take feedback or complaints about services that you are not happy with. You can call them on: 1800 035 544. Or you can call the National Relay Service and ask for 1800 035 544.
You can also do this online here: https://www.ndiscommission.gov.au/participants/complaints. You can also call the NDIA on 1800 800 110. You may seek support from family, a friend or an independent advocate when making a complaint.
For further information about disability advocacy please visit the NDIS Commission website.