Did you modify the dates of the logs or anything (in which case project-gc didn't notice the difference).
Either way the best thing to do is click the "support" button at the top right of the dashboard page, select "self support" and then enter the 6 GC codes in the refresh box at the bottom of the page.
If you don't know the GC codes then you can either look on geocaching.com (https://www.geocaching.com/my/logs.aspx?s=1
) or select "refresh found geocaches" but the changes may take longer to apply. There may also be a delay in other parts of the site such as your project-gc stats updating .