Trying to create rules when using extender

I purchased an RS700 app to be able to control access to the internet for my children. The router itself is amazing and I am able to set rules for bed times etc. However, our house is large and we needed an extender, so I bought the EAX80. The issue is that this has set up a separate network and I’m unable to create rules or bed times.

The only way I’ve been able to achieve this is to use an Amazon smart plug and turn the extender off at my desired time.

Surely there must be a way to use the router and extender as one single network and control what times people can access the internet?

Thanks in advance