Show an error message when changing quantity in the cart and tapping on the ‘Zur Kasse’ button.

Steps

1. Open https://www.wmf.com/de/de/
2. Log in t=with an account.
3. Add an item to the cart.
4. Tap on the ‘Cart’ icon > Tap on the ‘Zum Warenkorb’ button.
5. Tap on the ‘Menge’ to change the quantity of the item.
6. Tap on the ‘Zur Kasse’ button.

Actual result

The page show an error message ‘Something went wrong with your request. Please try again later.’ when a user changes the quantity of the item and taps on the ‘Zur Kasse’ button. Hence, a user cannot perform the following steps.

Expected result

The page shows information without any error message.