This error may appear for you if you have fewer columns in your .csv file than you have attributes in your ecomdash Import Format. Keep in mind that anytime you are uploading a file into ecomdash, the number of attributes in your format must match exactly with the number of columns in your csv file.
If you are getting this error, you will want to take a look at the format and the csv file to ensure they match up exactly. Once you have made the corrections, save and then attempt the upload again.
If you continue to experience issues, please reach out to firstname.lastname@example.org and make sure to provide the name of the import format you are using and a copy of the csv file you are trying to upload so that we can efficiently assist you.