I check in on Saturday and have been unable to check in online as well as on the app. On the app, it said a technical issue. I am not too concerned, we arrive midday, and I was planning to go to the front desk before the pool anyway. But I acknowledge that little things like that bug me and stress me out more than they should. I did get as far as room preferences and was hoping for a couple of minor requests, but could it be too late for that? Is it worth calling Disney during the day?
Have you tried from the website? In the past when I had an issue I found going to “private” in safari or incognito in Chrome will sometimes work.