To change your roundup account:
First, open your Qoins app. Then click on the upcoming payment from the Upcoming Payment card of the app. It will show the "Fix a connection error" pop-up, go ahead and click on "I'll fix this later" on the left.
Then tap the three-dot menu in the top right-hand corner. From there you will be able to select the option to "View contribution method" and then add a new roundup account.