Download the BT wifi app and setup access to btwifi through that. Then whenever you are in range of BT fin or BT wifi you will be able to connect.
Have you tried another BTWifi hotspot. It could be that the hotspot you are using is the problem and needs reset.
Just to clarify: It is the BTWifi signal that you are trying to connect to rather than trying to connect your devices by wireless to your own home network.
The reset has to be done by the owner of the Homehub that is transmitting the BTWifi signal. You are not able to do that unless it is your own Homehub that you are trying to connect to.
You should try and find another BTWifi hotspot such as at a cafe and try connecting to that to see if the problem is with your device.