Hello
Sorry for that question but I am spending time not finding the answer on Monday… so here it is.
I made a first import of data but I forgot 1 column
I expect when I reimport that I can just update that missing column…
But whatever I try, I cannot just get my existing elements with all date including the new mapped column.
What am I missing ?
Hello @EricChatry ,
Welcome to the monday community! 
You should choose the 3rd option here, and this will essentially update all of your previously imported items with the column you initially missed.
Hope this helps!
Giannis, Implementation Consultant at thespelas.com