Zigbee wired gateways

Thank you for accepting me into the forum. I’m new to zigbee and have just purchased 6 quimi TRVs a wired and a wireless gateways.
I’m struggling with range on two of the 6 TRVs. Can I connect another wired gateway to work on the same network to improve the range ? I tried a couple of zigbee smart plugs but they would not connect. Any help would be appreciated.

You don’t need a zigbee gateway for zigbee devices to work with home assistant. It’s better not to use gateways at all. You need a zigbee dongle ie. usb stick with antenna based on 26* chip that you plug in your computer running home assistant. This is called coordinator. Next you need routers, usually zigbe smart plugs, and off you go. You have a zigbee network.
coordinator

Some of the Zigbee USB sticks can be flashed with a firmware that makes them work as extenders.
You can also get devices already set up for that role, like the Ikea Zigbee extender.

You might have to reassign the devices to the extenders.