Approval Process Manager - A rule needs to be amended but it won't let me amend it as it says that there is another rule with the same name and priority. I've been through every single other rule and no other rule matches. I've changed the saved search to be searching for nothing, I've deleted the approval groups so it's not looking for anyone to approve. It's for a purchase order.

Not sure if this helps, but an eror message like that sometimes means that there is an inactive rule and it doesn’t show up on searches unless you specify both inactive and active.