Once a manager has marked your Sign Off as Pass, you may be required to go one step further and acknowledge that you have been signed off. You can tell that a Sign Off requires your acknowledgement by the status reading Pending under the My Tasks widget, as well as the fuel gauge that it resides under in the My Training tool.
To acknowledge these Sign Offs, simply click its name in either of these places to bring up the Sign Off page, click the box next to Acknowledgement, and press Complete.
Once this is done, the status of the Sign Off will change to Pass.