This is my first post, so please be kind if the post is not placed in the right location.
My home gateway / vivid wireless "4G" account is a few years old, but it seems that the speed is getting slow more often, which is quite frustrating.
Looking on the forum, it is recommended to have a look at RSSI and CINR parameters, so I tried to logon to 192.168.I.I as recommended, but got a fail -1 error when entering logon details.
I followed http://www.192168ll.website/
If it does not work, reset the router (view the manual for procedure). You will lose all your custom settings.
It is also possible that the address of the router has been changed. Perform a network scan (192.168.x.0 to 192.168.x.254, 10.x.x.0 to 10.x.x.254)