Wendy's online ordering only works for me once on each device. Please help!

The first time I ordered Wendy's online (a few months ago) it worked fine on the mobile website using my phone.

About a week later I tried again, but got this message (see picture). So I then tried to use the mobile app. However the mobile app will not allow me to login. When I use my email and password, it just loops back to the login screen. Same when I use Google to login, or Facebook.

So I went to my PC and was able to order on the website with no issue.

A week or so later I went to order again and got this message again. So I used an incognito window on my browser, created a new account with a different email and was able to place my order again.

A week or so later, tried again, same message again.

I reached out to Wendy's and was told "Were sorry you had trouble on our app. We added a credit to your account in our app for you to use for your next visit. Sounds great, but how does that solve anything? Let alone the fact that the credit does me no good if I can never log in to the app.

I've already deleted app, reinstalled, cleared cache, deleted cookies on the PC (incognito doesn't allow cookies anyway). Any ideas?

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