It isn't parental rights that are blocking your access to these sites. The error is actually coming from the site itself and not from the parental rights on the device.
All these sites use a reputation score to see if your external IP address is good, look at this it is more than likely that the sites are blocking you due to bad reputation which can be checked at https://www.akamai.com/us/en/clientrep-lookup/.
I am afraid that the issue you are getting is nothing that VM can help you with you will need to contact the sites themselves, in your example it is giving you a reference for asos which you will need to give them.
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