Help with Geckolib Mob

So i was trying to create a mob with geckolib animations using this tutorial: https://mcreator.net/forum/91485/tutorial-how-use-nerdys-geckolib-plugin?

and in a step with making a procedure, when i saved it error popped out, i tried to regenerate code like they said in the tutorial but it didn't work and error still persisted

here is a build log with errors that appeared:

https://pastebin.com/geafZ39u