OOOPS! Sorry Roser Park Watchdog...I just figured out how to edit an issue. This is how it works:
"My Account" > "My Content" > "Issues" > click on an issue and then look on the right side in a box there is an "edit" link. Click that and you can edit most things on the post.
I know this is not the answer you are looking for, but I don't think you can edit a posted issue. I'm just a user like you but I've looked into this and not found a way to edit content. I would just add corrected content as a comment under the initial post. You can also flag it and you will have an opportunity to explain why you are flagging it.