Sane had agreed a new deal with Bayern to 2028, but is yet to put pen to paper and has now changed agents.
The agreement has stalled as Sane is having second thoughts on signing a deal which will see him take a €4-6m-a-year cut on his current salary, says Sky Deutschland.
In a meeting on the weekend with Bayern chiefs, Sane informed directors he was changing agents from Win11 to Pini Zahavi.
As such a renegotiation over the contract would be needed. It's suggested Sane will now not accept pay-cut unless a hefty signing bonus is included in Bayern's offer.
CEO Jan-Christian Dreesen told Abendzeitung: "Leroy is having a good season. Zahavi is an experienced agent, not always easy to negotiate with. But that's just how it is. We'll see how it goes. Max Eberl is doing an excellent job with Christoph Freund."
President Herbert Hainer struck a similarly optimistic tone, adding: "I don't know his motives. We've usually almost always reached an agreement with Zahavi. I'm an optimist by nature. Leroy has said often enough that he wants to stay."
Watching developments are several Premier League clubs, including Arsenal and Liverpool.