If you cannot get in, start with connectivity diagnosis. If you can play but responses arrive late, compare server nodes and collect a delay test. These tools gather evidence; they do not guarantee a repair.
Sources
We checked these official pages and wrote the steps in our own words. Follow the publisher’s page if it has changed.
Marvel Rivals: network analysis tool guideMarvel Rivals: server selectionMarvel Rivals: release FAQ and support contactMarvel Rivals: official newsSteam: Marvel Rivals requirements and languagesJapanese version of this page