I am watching La casa de papel (in Spanish with subtitles in my language because my Spanish is not that good), and I have noticed that two characters, father and son (Moscú and Denver, for those who know the show), speak what I believe is some dialect or variant of Spanish, whose most evident phonological trait seems to be the fact that they omit several “s” sounds. They omit them pretty systematically at the end of the words and sometimes in the middle: es > e; estar > etar; vamos > vamo; entonces > entonce, several plurals (pelotas > pelota; palmeras > palmera), and so on. Estás is almost ta. I hear other omissions too (todo > to), but it might just be due to speaking fast.
Does anybody know which dialect or variant of Spanish might that be?