You can see a "vacant" shift on your roster, but you can't take it? Typically that's because the hospital has not placed the shift in the market. If that is what they want, they need to place the shift on the market. So instead of it looking like this:
It looks like this:
This "gift" icon means you can take this shift, without having to swap for another shift.
It is also possible you can't take the shift because you don't have the correct role, team or skills to do this shift, or the shift is in the past.
If you think you meet all the requirements, and you cannot see the "gift" icon, please contact your roster administrator