According to L'Equipe and other French sports media, the dressing room is divided in 2 groups. Group 1 is composed of the Brazilian players + Kylian Mbappe who was "adopted" by the Brazilians. Group 2 is composed of the non-brazillian South Americans(Cavani, Pastore, Di Maria and Lo Celso).
Group 1 is accusing Group 2 of not trying hard enough, while Group 2 accuses Group 1 of having excessive privileges. Both groups are right in their allegations. The culprit for it all is Unai Emery of course, who has already proved he's not a very good disciplinarian and doesn't know how to handle a team with 11 stars.