The problem you are experiencing is related to account migration. When logging in to the app, Migros Online tries to connect your Migros account to an existing Migros Online account, but is unable to do so. Solving this problem is straight forward:
- Go to shop.migros.ch
- Login with your Migros Login
- Follow the instructions carefully. If you have an existing LeShop account, you’ll be able to link it to your Migros account. Otherwise, simply complete the registration information.
- Once complete, you should now be able to login with the Migros Online app using your Migros Login