The German giants' public pursuit of the 24-year-old last summer ended without a deal being struck between the clubs.
Sane has not played for City all season after damaging his knee ligaments in August's Community Shield win over Liverpool, but Bayern chiefs refused to rule out a future move, potentially as part of a swap deal.
However, the Manchester Evening News claims that the coronavirus pandemic - forcing the shutout of Europe's top leagues - has further complicated matters due to uncertainty over when the window will open.
Bayern also supposedly feel the Germany international is not showing enough commitment to joining them, sparked by his decision to change agent at the turn of the year.
Sane recently opened up on the "longest and hardest" journey of his career to recover from a long-term knee injury. body check tags ::