PacePro malfunction

Sometimes PacePro works seamlessly and sometimes it doesn't work at all. It's very annoying when you are about to use it on a race and the feature doesn't work. 

When I press the start button, the watch screen displays "New pace for kilometre 2" and then it'll show me the PacePro screen but the overall distance left bar won't update and it won't display how much ahead or behind I am. 

For this reason, I don't use it anymore when I go out for a race, but I'd like to be able to rely on this in future races to pace myself. Are there any fixes to this issue? I have tried resetting my watch, updating and deleting and recreating new pacing strategies for PacePro but I'm getting no luck. Any help is appreciated!