Hello there Tanja,
Welcome to planDisney! I'm happy to hear you're planning a trip to the Disneyland resort next month, but not so happy to hear that you're having some tech issues in getting your credit card set up in the
Disneyland mobile app - that is no fun!
It sounds to me like you've tried all the basic troubleshooting tips that I would initially try if it were happening to me - specifically trying other cards. Did you use these credit cards at all on the Disneyland website? If they worked there, but not the mobile app then at least we're one step closer to figuring out where exactly the problem is.
At this point, I would recommend
reaching out to a Cast Member. You might want to start with the Guest Information line (+1 714-781-4636 in case my link doesn't work for you) or you could try the Website Support line (+1 714-520-6222). I'm hoping that they can give you a bit more clarity about what might be going on.
I have heard that the Disneyland mobile app doesn't work internationally in every country, so it's possible that might have something to do with it, but it might work fine by the time you arrive at the Disneyland Resort. However, I wouldn't want to count on that, which is why I'd recommend speaking with a Cast Member before your trip.
I'm hoping that will help as you continue to plan your trip! Thanks again for your question, Tanja. Feel free to stop on by again if you think of any follow-ups. We'd love to help!
Have a Magical Day,
Greg