Video Not Working

I just purchased the Hook theory 1 book from the Google App store for Android and I am not able to open the videos. Its a black screen , I can see the play button but it won’t activate the video. I went to settings and it said to download video player which I did but that still doesn’t work. Please help. I have a Samsung Galaxy A52 5G, the phone should have the capacity to handle this. I want to get a subscription to the Hook theory app but until I get this straightened out, it probably doesn’t make sense because I won’t be able to use it. Right now the screens all black and there’s 4 little colored dots rotating around in a circle