Try this:
1. Insert your Navionics card into the card reader on your computer.
2. Open the folder to view the files.
3. Go into “Navionic > Charts”
4. Delete the “UGC” folder.
5. Also, delete the files within this folder with the following file extensions (.ugc, .uk, .ck)
6. Perform the Freshest Data Update again. Please only select the “Nautical Charts” option, and disable the “Community Edits” option.