combinatorics – k-permutations of NON DISTINCT elements for example the word ‘Mississippi’

I’m a little bit confused about permutation. Consider the string Mississippi. I need a k-permutation without repetition of the string. I know that Misp is a compatible k-permutation. However, is Mispp a good one? On one hand it is not, because p in Mispp is shown twice. On the other hand, it is, because the original Mississippi contains p twice, so each of the p is shown only once.

Same with n-permutation without repetition. Is pipiMissssi a “permutation without repetition” of the original word?