So hackers can disable command blocks with a game rule command like /gamerule commandblocksenabled true or false in realms and it give them a HUGE advantage to protect the realm from being hacked like for say you have a have a command block that kills command block minecarts and they turn the gamrule to false so then your realm is gone someone has been harassing me by hacking my realm so that's how they're doing it so PLEASE FIX THIS mojang:
Check your player permissions. The hackers likely have operator permissions, likely due to the default permissions being operator. Change the default permissions to member, as well as those that you suspect of changing the rule. If the hackers are not operators, then they should not have the ability to use commands, and should not be able to change this game rule.