I'm very displeased with Viasat,, it takes forever for something to download , when we do have Wi-Fi. Our speed is terrible. Should have service call to fix all problems, at no charge, as much as we are paying for this service.
How far are you from the modem? Does wifi have to travel through several walls? Are speeds fine with a wired connection? If wired connection is fine you most likely need wifi extender to where you are trying to access wifi.