BuyCraftPM Error?

Hey guys i found an error in buycraft when im typing my secret

Code:

[Thread thread / CRITICAL]: Unhandled exception executing command 'buycraft secret ad91bac0a94ef0854c41b91d124da2bfb4c35309' in buycraft: Call to undefined method_checkmine \ Server :: getScheduler ()

11:46:25[Server thread / CRITICAL]: Error: "Call to undefined method_checkmine \ Server :: getScheduler ()" (EXCEPTION) in "BuycraftPM.phar / src / Buycraft / PocketMine / Commands / BuycraftCommand" at line 62

11:46:25[Server thread / DEBUG]: # 0 src / pocketmine / command / SimpleCommandMap (258): Buycraft \ PocketMine \ Commands \ BuycraftCommand-> execute (pocketmine \ command \ RemoteConsoleCommandSender object, string buycraft, array Array ())

11:46:25[Server thread / DEBUG]: # 1 src / pocketmine / server (1955): pocketmine \ command \ SimpleCommandMap-> dispatch (pocketmine \ command \ RemoteConsoleCommandSender object, string buycraft secret ad91bac0a94ef0854c41b91d124da2bfb4c35309)

11:46:25[Server thread / DEBUG]: # 2 src / pocketmine / network / rcon / RCON (103): beanmine \ server-> dispatchCommand (pocketmine \ command \ RemoteConsoleCommandSender object, string buycraft secret ad91bac0a94ef0854c41b91d124da2bfb4c35309)

11:46:25[Server thread / DEBUG]: # 3 src /checkmine/network/concon/ RCON (77): checkmine \ network \ rcon \ RCON-> check ()

11:46:25[Server thread / DEBUG]: # 4 vendor / pocketmine / snooze / src / SleeperHandler (120): http: //mainmine \ network \ rcon \ RCON> pocketmine \ network \ rcon \ {closure} ()

11:46:25[Server thread / DEBUG]: # 5 vendor / pocketmine / snooze / src / SleeperHandler (82): pocketmine \ snooze \ SleeperHandler-> processNotifications ()

11:46:25[Server thread / DEBUG]: # 6 src / http://cheapmine.com/server (2259): http://www.patchmine \ snooze \ SleeperHandler-> sleepUntil (double 1538127985.467)

11:46:25[Server thread / DEBUG]: # 7 src / #chainmine / server (2134): #mainmine \ server-> tickProcessor ()

11:46:25[Server thread / DEBUG]: # 8 src / #mainmine / server (1700): #mainmins \ server-> start ()

11:46:25[Server thread / DEBUG]: # 9 src / pocketmine / PocketMine (243): http://chainmine.com/server-> __ construct (BaseClassLoader object, pocketmine \ utils \ MainLogger object, string / home / minecraft /, string / home / minecraft / plugins / )

11:46:25[Server thread / DEBUG]: # 10 /home/minecraft/pocketmine.phar(1): require (string phar: ///home/minecraft/pocketmine.phar/src/pocketmine/PocketMine.php)