Flash image fail

We are using an image in slot 1 of more than 40GB, and flashing an .img to the rest of the slots (15), we are having problems and all the copies are the same, missing data in some of them.
we are using etcher pro version 1.14.3

Do you know if this is solved in a higher version, if there is a higher version it should be installed automatically by WIFI? currently nothing is updated?