Sorry for the lack of info. Cornerstone now uses “Translate Independently”. This means that your old Spanish page is no longer connected to Cornerstone so you would need to edit first your English page then switch to Spanish, then you would need to translate again.
In the screenshot below, there is no “Edit Pagina” link showing that it is not connected to Cornerstone.

We understand this is inconvenient but this is regretfully necessary because of technical conflicts in the previous versions.
To demonstrate what I mean, I manually translated your page https://www.mango.org/es/professionals/industria/ again. After saving the new Spanish page in Cornerstone, you’ll see that the “Edit Pagina” link is now back. Please see the secure note of the recording I did to show you a way to translate a bit quickly.

I left out the Contact section for you to translate so you get the idea. You would also need to do this for other pages.
We’re very sorry for the inconvenience this has caused you.