Black screen when no face detected - urgent!

We have downloaded an effect from the store - https://www.store.deepar.ai/product-page/dog-ears. The problem is that when a face is not being detected the entire screen goes opaque black. This is no use to us - in fact I can’t see how it would be any use to anyone!
I have looked at the effect in studio and have adjusted the effect so it can detect multiple faces, but I just cannot see how to fix this issue.
Any help or suggestions are most welcome.
Thanks
Stephen