Welcome to the community, @Alberto_Leotta!
You should probably contact support@airtable.com about this, and report back here with what they tell you.
Even though you deleted your data, I believe that it still counts towards your storage limits for a year so you can restore that data later if you’d like. So I think you need to contact support to permanently delete the stuff you deleted, in order to clear up space.
It would be nice if the trash can didn’t count towards our storage limits, but I believe that it does. I’m not 100% certain on this, but I think it does. Please report back here with what support says!