@Mihu 

  > better hardware from a different vendor.

Do you have any recommendations? Any one that for sure have mac address whitelist functionality?

The M9's has worked great, but, as everyone here has realized, every screen addicted

nine year old can circumvent the "parental control" by getting new mac addresses.

The M9's wil go to the bin.

I wonder if this feature will ever be added. TPlink has another product line called Omada that offers this feature and so much more. I guess they just want us to switch to Omada if we want more rather than adding additional features to this one. I regret going for the decos and not the omadas. Omada products cost more but hey I think they're worth it. I've tried some of them and I can say they're way way better than the decos.

  @Svettbralla 

Try looking at Tplink omada line. It has all the features that you mentioned here and maybe more. This is targeted for business/office environment but is suited for home environment as well, especially for those who want more control over their home network.

  @D10N 

I wouldn't buy TP-Link products again after seeing their disregard for their customers for the last 4+ years over this issue.

  @Kevin_Z these posts are from 2019 and 4 years later Dexo has STILL not made this an option???? Poor customer service

It's pretty pathetic to see TP-link not providing an enhancement to the application of either defaulting the new connections to a default "least privilege" profile or the ability to block the unknow connection. I don't think it's a big ask but its been so many years and they haven't released this feature. Parental control is kind of useless if these features aren't there.

  @Lawrence-C  I use the guest net for the siblings and turn it off when I notice slightly attempt of mac spoofing unfortunately it affect all using the guest. But what i miss is a simple "approve "or "deny" option. before any connection. In addition there should be an captive portal option for the guest net where this could easely be incorporated like "request for connection" The app is not intuitive and appears to me difficult to navigate in and the parent controll do not allways work when block or release mac.

Here's my Fix to this debacle: 

I plugged another spare old router into the second port of one of my M9's.

Then my kid (who had two devices that keep changing the MAC) was only allowed that password!

And best thing is, i can now restrict that router in the family section for sleep time & hours online!

Shame on you for not fixing this yet TP-Link...