Hello Judy,
It seems that the source of your issue is your Internet Service Provider, Viasat.
https://community.viasat.com/viasat/topics/cant-watch-streaming-movies
Depending on which plan you have you might be hitting your bandwidth cap and everything you stream is being throttled, a user in that forum topic I linked stated using a VPN has made streaming less of a struggle. Might be in your best interest to try using a VPN service if Viasat is your only option for high speed internet.