@Jamelex11 Check this guide - https://www.cable.co.uk/broadband/guides/own-router/ for using third party router with your Virgin Hub 3. "Virgin Media Virgin says that in order to use your own router...

@shepp Have a look at this thread.

Try positioning the extender in around the half of the distance between your main router and the office for maximum effect.

Have you rebooted the router to force all your wireless devices to reconnect ?

@Tihomir Agree on that. When @Kevin_Z is around, he may advise on that issue for both of you.

@Tihomir This solves many issues as well. Do that by the reset button on the back. Then re-configure from scratch.