It’s hard to understand that a business partner for 15 years and after dozens of millions of dollars spent can kick you in the @@s and ghost you without any explanation.
This kind of behaviors from large corporations have to stop.
Facebook's cash flow is enough that even this company's revenue is a rounding error on _weekly_ numbers.
In other words, FB don't care, don't let the door hit you.
If some player has a few billion in FB revenue at stake, I'll bet they can at least reach a first tier CSR.
If they were an actual business partner, you could rely on the terms of the contract the two of you arrived at to define your partnership to give you recourse, assuming your lawyers were competent.