I had trouble uploading a .csv file from MyHeritage TO MyHeritage (separate account). I opened the .csv in Excel, removed all the header rows, leaving JUST the data, then saved as .csv file again. The file with ONLY data in it uploaded. If you have a good .csv and the site you're using claims to accept .csv, try the edit that I did so that your file has nothing but the data in it. Only takes a minute to edit and might help. Good luck.