I tried multiple times. Every time the file downloads and it fails during verification. Every other app downloads and verifies successfully. I think they might have changed their signature? When I look their sha256 I get this key:

e0735a70d3439f6e5739a2b9e2ddd2d4bec18b679ac1a614a05ecacc8e1d2820 1.9.57.apk

If i am not mistaken in your app it shows another key...