There is no multiplayer button in the game

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please help with the problem
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reinstall BeamMp if not check your wifi

Same issue. I’ve registered and have reinstalled BeamMP twice and clearing cache.
The game launches to the regular single player UI in the main menu.

Fixed the issue by enabling mods from the main menu>Deactivate all mods>Reactivate the BeamMP mod
See Multiplayer button missing on main menu - Support / Client Support - BeamMP

Wrong. It’s a common bug, you just have to enable the BeamMP Mod again.