If you've been having issues with Dragon Ball FighterZ in certain areas, you should know that Bandai Namco is fully aware of the situation and is currently working on a repair. Below is a video released by the company featuring the game's producer Tomoko Hiroki as she explains that they will not rest until they fix all of the issues within the game. The upcoming patch is set to resolve two key areas, specifically being disconnected from the Ring Match as frequently as it has become (which will be released before the end of February), while a second patch in March will focus on all the odds and ends that have been making multiplayer matchmaking a problem along with some other key areas.
I don't think we'd be the first people to say that the entire online matchmaking system is slowly becoming garbage. We'd prefer to see something more like Capcom's system that's being used in Street Fighter V, which you'd think Bandai Namco would love to work with seeing as how they already use variations of that system with Tekken 7. Whatever the reasoning for the issues, it's clear that it might be best to retool the entire system in Dragon Ball FighterZ and get a new server in place.