Error trying to give the player a Pokedex

In my players home, I have an event set up to give you a pokedex, its a script event but when I then test it I get this error

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Pokemon Essentials
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Exception: RuntimeError

Message: Script error within event 5, map 8 (Player's Home):

Exception: NoMethodError

Message: (eval):2:in `pbExecuteScript'undefined method `pokedex=' for nil:NilClass

***Full script:

pbUnlockDex
$trainer.pokedex=true


Interpreter:243:in `pbExecuteScript'

Interpreter:1606:in `eval'

Interpreter:243:in `pbExecuteScript'

Interpreter:1606:in `command_355'

Interpreter:494: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'



Interpreter:276:in `pbExecuteScript'

Interpreter:1606:in `command_355'

Interpreter:494: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'



This exception was logged in

C:\Users\Blue\Saved Games/Pokemon Essentials/errorlog.txt.

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OK
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$Trainer.pokedex=true

Capitalization is important.