Nil?

I'm working on a project, and whenever I try to enter just one (not entering any...) i get this...

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Exception: NoMethodError

Message: undefined method `unlock' for nil:NilClass

Interpreter:512:in `command_end'

Interpreter:295:in `execute_command'

Interpreter:193:in `update'

Interpreter:106:in `loop'

Interpreter:198:in `update'

Scene_Map:103:in `update'

Scene_Map:101:in `loop'

Scene_Map:114:in `update'

Scene_Map:68:in `main'

Scene_Map:65:in `loop'



This exception was logged in

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OK
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