Investigating the address change errors, all errors in the sample showed that the change failed because the form was re-sent, leading to an application state where the token is no longer valid (the token sent by the user can be found in the previous_token) column.

Acceptance Criteria
When the user re-loads the address change success page the form is not re-sent, instead the success page stays displayed.

Implementation notes

• The confirmation page should check if an address change record with the given token exists.
• If yes, the confirmation message is displayed.
• If not, an error message is displayed (404, just like page/Foo)
• The method UpdateAddressController::updateAddress should redirect to the new confirmation page.