According to Spanish newspaper El Diario de España.
Bayern
For Barcelona
middle period of a tripartite provincial exam (in former times)
De Jong (ethnic group)
Interest in the deal is starting to fade and they are skeptical about the deal.
Previously Bayern were interested in two players from Barcelona's squad, Araujo and De Jong, and their interest in the former remains the same at the moment, but their interest in the latter has shifted.
De Jong's high salary and long contract is a problem for Barcelona, and likewise stops Bayern's interest in him, especially considering Bayern haven't settled on a new manager yet.
De Jong has not been at his best this season due to injuries and his performances have not convinced the Bayern hierarchy. If Barcelona decide to sell De Jong, they will need to wait for offers from other clubs, such as Manchester United, who are also interested in him.
It's worth noting, however, that current United boss Ten Hahn would rekindle Bayern's interest in De Jong if he were to go to the club, as the pair had a fantastic partnership at Ajax.