TMZ broke the story ... Mary J. Blige and Steve Stoute Foundation for the Advancement of Women Now is being sued by TD Bank over a $250k loan it took out back in June 2011.

TD Bank claims it loaned FFAWN the money in June 2011 -- and FFAWN agreed to repay it by December 2011 ... but so far, TD Bank has only received $368.33.

Now, Mary tells us, "As Founder and CEO of FFAWN, I am ultimately responsible for anything that goes wrong. The problem is that I didn't have the right people in the right places doing the right things. This should have never been allowed to happen, but it did and now we are fixing it."

The singer says she's working tirelessly with a new team of experts to "get the Foundation back on track, rectify outstanding issues, and make good on all of FFAWN's obligations."