[17:47:11] [Server thread/INFO]: Loading Prealms_BuildBattle v1.14.0 Fatal error: Declaration of Kai\BB:nCommand(pocketmine\command\CommandSender $player, pocketmine\command\Command $cmd, $label, array $args) must be compatible with pocketmine\plugin\PluginBase:nCommand(pocketmine\command\CommandSender $sender, pocketmine\command\Command $command, string $label, array $args): bool in phar:///home/minecraft/plugins/BBattle.phar/src/Kai/BB.php on line 31 [17:47:11] [Server thread/EMERGENCY]: An unrecoverable error has occurred and the server has crashed. Creating a crash dump [17:47:11] [Server thread/EMERGENCY]: Please upload the "/home/minecraft/crashdumps/Thu_Feb_27-17.47.11-CET_2020.log" file to the Crash Archive and submit the link to the Bug Reporting page. Give as much info as you can. error plss i need your help guys
Please put code and/or command line output inside of code blocks (use the "+" button to add one). It makes them easier readable and prevents the text from getting converted to emojis. As for your issue: The plugin is very outdated, contact the author or ask someone else to fix it (but only if the author doesn't reply).
You are trying to run an outdated plugin. Outdated part is in onCommand() function. It must be written in same format as it is declared in abstract class pluginbase. so just add string before $commandLabel and :bool after )