[Scripting Question] i need help with this Script.

[Golden cheetah]

please help me with this. this is the problem that happened to me with the battle tower. everytime i try to start the challenge. this error comes



[Pokémon Essentials version 18.1]
Exception: RuntimeError
Message: Script error within event 4 (coords 16,3), map 55 (Battle Tower):
Exception: NameError
Message: PBattle_OrgBattle:489:in `start'undefined local variable or method `t' for #<BattleChallenge:0xd6886d0>

***Full script:
pbBattleChallenge.start(0,7)


Backtrace:
Interpreter:197:in `pbExecuteScript'
(eval):1:in `pbExecuteScript'
Interpreter:1458:in `eval'
Interpreter:197:in `pbExecuteScript'
Interpreter:1458:in `command_355'
Interpreter:359:in `execute_command'
Interpreter:155:in `update'
Interpreter:102:in `loop'
Interpreter:158:in `update'
Scene_Map:162:in `update'


Backtrace:
Interpreter:246:in `pbExecuteScript'
Interpreter:1458:in `command_355'
Interpreter:359:in `execute_command'
Interpreter:155:in `update'
Interpreter:102:in `loop'
Interpreter:158:in `update'
Scene_Map:162:in `update'
Scene_Map:160:in `loop'
Scene_Map:169:in `update'
Scene_Map:229:in `main'