I found a knowledge base article on this. The call log gets corrupted. The only way that I found to correct it was to wipe the device and start over. If you have the desktop software installed, make a backup of your device and restore it once you finish wiping the device.
On your desktop, click "Messages." find everything that's orange (or yellow, whatever) and click on it. Then click your reverse button, and that call (or message, or email, or whatever) will not appear at the top of your desktop