slim-3-authentication | A Slim 3 authentication system | Authorization library

So I've built a simple API with Slim framework, while using one Middleware for validation from here https://github.com/Respect/Validation via a function as followed through this guide:

https://www.codecourse.com/lessons/slim-3-authentication/769
https://www.codecourse.com/lessons/slim-3-authentication/770

Everything seems to be alright except of one specific thing:

By this guide I should be able to validate my forms and their input and then on my Twig page print these errors for example by doing this {{ errors | json_encode }} (for testing), the problem is that even though the validate function itself works as it should I can't seem to get the errors as they always return null.

By using var_dump I've noticed that the "errors" are there, but the format seems a bit different than the one shown in the guide video as in my var_dump there seem to be an extra array? (not sure) showing NULL, and only after that there are other arrays containing these errors so I would assume that would be the reason of why it's not working?

Here is an example of what I get when I var_dump it: