I noticed that my ANT took two workouts from my 610 and deleted them from the watch, but didn't connect with the WEB. I have fixed the web connection issue, but anyway to go back in and get the data back to Garmin Connect.
Thanks
If you are using the ANT Agent, the .fit files should be stored on your computer. This page describes where to find the History folder. If you go up one folder, you should see the Activities folder. Find the appropriate .fit file in there (they have date/time stamps) and try to upload it via the import/upload link. Chances are, that upload will fail because the .fit file is corrupt (the original reason the upload failed). If it does fail, you'll probably need to use the Fit File Repair Tool or this website to fix it.