Yes?
Look, I hate to be "I told you so", but this shouldn't be a surprise: this is how Facebook has treated partners all along.
Remember when the big thing that drove engagement on Facebook was games? Zynga was making a mint on that. Until one day Facebook's metrics showed that the constant "Help my farm!" updates were pissing people off; they flipped a switch and games disappeared, and Zynga got kneecapped. I think it still technically exists, but it's a shell of what it was.
Then it was all about sharing as many news articles as possible, and Facebook built all these relationships with news publishers. That lasted until fake news and Facebook deciding people want more status updates from friends, and the publishers all got their traffic slashed with naught but a "I am altering the deal. Pray I don't alter it further."
When your business lives on Facebook's platform, you exist at their whim. As soon as they decide you're no longer useful, you're cut off. You really should've had a plan for this.