Netgear Nighthawk AX40 and TP-Link Powerline adapters

Hi,
I have been tearing my hair out over this.

I have a Nighthawk AX40 which has a TP-Link Powerline adapter plugged into it.

This feeds an internet connection to 2 wireless TP-Link Powerline adapter (the walls here are very thick) at the back of the property.
I also have a 3rd non wireless one for the Sky Q box as it refuses to sustain a wireless connection.

The issue that I have is that when the adapter is plugged into the router, it causes the internet to drop for all devices.
It doesn't happen straight away and can take between 5 - 15 minutes to occur.
I have reset the powerlines, reset both the router and modem to factory with no joy.
When the connection drops, I cannot log into the router's interface to see what is going on nor can I log into the powerline interfaces.
It seems to be a conflict that is created when the powerline is plugged in but I cant see where it is occuring.

Can anyone shed any light on this as without the powerline adapters, there is virtually no internet access at the back of the property.