Breakout room hang or freeze

hi, i need solution with zoom breakout room. i have large meeting add-on with 1000 participants, when in-meeting all of my participants join on main session and i create 5 breakout room with option my participants can select and join one of my breakout room that i have been made, on firstly i open breakout room its working fine, the participant can join on breakout room, and i (as host) can assign participant to breakout room, but not for long time since i open breakout room, my breakout like hang or freeze, my participant cannot join to breaokut room (when they click anfd join to breakout room nothing happen) and i (as host) cannot assign them too (the assign button is there, but when i assigned them, nothing happen too). this case happen 2 time in same day, and i have updated version of zoom meeting client to be host. is this an issue ? or there is be a setting that i missed ?