Crashing while exporting with paid Rush app

My Premiere Rush is continuously crashing at the very beginning of exporting a video of around 20 mins in length. The video has got no effects and I have used only a basic color correction to all my footage. I am using the paid app on my iPhone 11 and this video is very important as this needs to be made before my deadline. Please fix the issue or return my money if tou can’t deliver what you promise.