Bulk send email error message

I am new to adobe sign and this has been quite more difficult than I would have liked or was expecting.  I'm sending bulk messages using a CSV upload.  I've already read through the tutorials on everything and have even spoken to/ had someone virtually man my pc to figure out this error.  It does not occur all of the time, but at least half the time I have an error message saying that my "bulk send messges require an email recipient".  My field to pull this data is accurate and I also have emails listed as per the sample CSV file.  Messing with it today I was able to save a file and upload.  When I added more data (did not delete a single thing) it gave me this error message.  I was also able to upload a file but after I resized the rows (not changing an data at all) it gave me this error message.  This has happened (seemingly at random and far too often) throughout the past couple of weeks of trying to get this set up as needed.  Any help is appreciated.