Family sharing is having multiple accounts use the same game purchase on Steam.
Anyway, you're not the only having this issue.
https://www.reddit.com/r/RocketLeague/c ... 4/dzyg2yc/
https://www.reddit.com/r/RocketLeague/c ... ff_season/
https://www.reddit.com/r/RocketLeague/c ... on_anyone/
https://www.reddit.com/r/RocketLeague/c ... _disabled/
afaik, after the update Rocket League hates your connection and doesn't want you to play Ranked. Try to get in touch with their support.
https://support.rocketleague.com/hc/en-us/signin