Good Morning @Johnandgem and a very warm welcome to you!
Sorry to hear of the issues with the speed.
Are you able to run a speed test via a Cat 6 Ethernet cable, and with the hub in modem mode?
This will tell us what speed we have going into your property. If this reads as the subscribed speed (or slightly above) this may be a case of an issue with the Wi-Fi facility, or the set up of your home to accommodate a Wi-Fi connection.
If this is below the subscribed speed, this may be an issue outside the property that needs to be rectified
Kindest regards,
David_Bn