Capacity issue with Portfolio, and advice/support would be much appreciated.

[Josie Lawthom]

I am having an issue where an error message shows that one of my team members are over capacity when the capacity view still says he has availability. Am I missing something? Also, with another member of the team, he has a large amount of availability but I can't seem to allocate any work to him even though he has the required skills.  Even when I do this manually it shades out his icon and says, the chosen member doesn't have the skills or availability to do this task.  I know on the screen shot below I have hours 0 but under those names I have added an exception to say that they are available for the next 3 months.