If you go to the Files tab you can download the raw data files from Slingshot. If you download and unzip the file that has a status of "Processed" that will have an "Advanced.xml" file. If you open that file you'll see the Customer and Field are blank. There's nothing we can do if there are no values here.
My best suggestion would be to e-mail the files to Raven support and see if they can provide any suggestions for help.
Regarding how to fix the data in Connected Farm, we do not have the ability to change the field on a task today. However, this is planned for the future.