you for reaching out on the community and telling us about your issue. I do
apologize for the issue you're having. Are you trying to edit a manual account or a downloaded account. Either one you should be able to adjust the interest rate by clicking on the account and in the top right of the register you'll see the interest rate and an edit button to allow you to adjust the interest.
let us know if this helps resolve the issue for you or if this doesn't solve exactly what you're looking for.