[Error] Playtest crashes when I change learnset.

[KDJkai]

My Pokémon Essentials game has essentially hit a roadblock.
I want a gift Charizard to have a more diverse moveset and therefore thought of teaching it Crunch, Air Slash and Dragon Breath. When I changed the data for the moves Charizard could learn it gave me an error.
[Pokémon Essentials version 19.1]

Exception: ArgumentError
Message: Invalid argument passed to method.
Expected nil to be one of [Symbol, GameData::Move, String, Integer], but got NilClass.

Backtrace:
015:Validation:29:in `validate'
101:GameData:26:in `get'
342:Editor_DataTypes:1059:in `block in format'
342:Editor_DataTypes:1057:in `each'
342:Editor_DataTypes:1057:in `format'
342:Editor_DataTypes:1514:in `block (2 levels) in pbPropertyList'
342:Editor_DataTypes:1512:in `each'
342:Editor_DataTypes:1512:in `block in pbPropertyList'
342:Editor_DataTypes:1478:in `loop'
342:Editor_DataTypes:1478:in `pbPropertyList'

I have no idea how to solve this, but I've tried it with many pokémon discluding Charizard and none of them want to change their movesets, I even tried to go into the file to edit it manually but opening it with notepad meets me with chinese and opening it with notepad++ just gave me strange strings of letters. I really want to know how to fix this Charizard's moveset!