Really sorry for the late reply @Manuel. We are experiencing a high volume of enquiries & may take some time responding. You cannot setup parental control through the Optus modem I`m afraid. You need to set it up on your own device (laptop, desktop etc) by using external parental control software. Check out this link with more information. If you need help with anything else let us know.
Hmm, I'd recommend having a chat with our Faults team on 131344 or through Live Chat so we can look into this further.