[Resuelto] Translations are not working

Background of the issue:
I am struggling with 4 things in WPML on my site enlace oculto. I am trying to manage translations and templates effectively.

Symptoms:
Translations are not working. I can't open translations and jobs, there's an error like on the screenshot enlace oculto.

Questions:
Why can't I open translations and jobs in WPML?
How can I translate the paragraph in the header (top bar) of my website?
Why did many pages lose their templates after translation?
How can I fix the broken SALE page after translation?