Hi!
I’m pretty new to anki I scrolled for a bit here and it looks like no one yet recently had the same issue with me.
Whenever I import from a csv file my notes suddenly duplicate like all even though they are different questions and answers too.
Before we dig too far into what is happening with your import file – try running Tools > Check Database and see if that makes the copies go away.
If it doesn’t – are you being careful to choose the correct Import options for what you want to have happen?