Very bad service

I have been struggling for a very long time. They keep showing me back to the app. The app dont allow large files. I have submitted docs so so many times, yet they keep on rejecting the document. Then it is that, then it is this. It really is a bit of a joke. And then they cannot even email me to inform me of what is needed. Just use the app they say. Without any success. It just keeps on coming back....