"Unknown error" – FlixBus & FlixTrain Review

I keep getting an error through the app. Tried the desktop. Same error. I called customer service and all they can say is clear the cookies and download the app again. Keeps saying error. They told me to go to one of their stands- it would be nice if I could get there, but I can't since I can't boom a bus ticket. Customer service was pretty useless. Even though it's their app and their website still want to charge phone fees for booking over the phone. If you fix your app I'd gladly never call you and book on my own.
Review by Gpmss on FlixBus & FlixTrain.