WiFi extender not working by hub 5

Ex3110 is the exact model I don't know if I've done something wrong I must've because this won't work with my bt hub 5 it happened after I did the online setup I went through everything i connected to both 2.4 and 5 GHz networks whatever they are? at the end it said I wasn't connected or whatever but it made a new network nonetheless it's just my same hubs name with 2GEXT at the end which doesn't really do anything when I connect to it basically I must've set it up wrong or it doesn't work with the bt hub I can't get back to online installation either I don't think, anybody find out how to do this please and thanks for any help