[Error] Anyone know what this error means and how to fix it?

[TheCandyFurret]

I'm currently transferring my game from V18.1 to V20.1 and I came across this error. I'm unsure how to fix it.

[Pokémon Essentials version 20.1]

Exception: NoMethodError
Message: undefined method `<=' for nil:NilClass

Backtrace:
381:Compiler_CompilePBS:1486:in `block (2 levels) in compile_trainers'
381:Compiler_CompilePBS:1485:in `each'
381:Compiler_CompilePBS:1485:in `block in compile_trainers'
380:Compiler:242:in `block (2 levels) in pbCompilerEachPreppedLine'
380:Compiler:234:in `each_line'
380:Compiler:234:in `block in pbCompilerEachPreppedLine'
380:Compiler:231:in `open'
380:Compiler:231:in `pbCompilerEachPreppedLine'
381:Compiler_CompilePBS:1439:in `compile_trainers'
380:Compiler:774:in `compile_pbs_files'

Help is very much appreciated!