Apparently, when someone suggests an edit and you accept it, the original version of your translation remains in the list of translations for this sentence together with your edited version. I say apparently, because I am not sure: I wanted to verify this behavior for a sentence of mine for which I accepted a modification, but could only see my own and latest translation.
Obviously, this behavior is very annoying in that people keep seeing the old (mistaken) versions and keep suggesting edits.
So, I was wondering if anyone could confirm this behavior. I think it is also a good idea to suggest to Duolingo to change this if this is indeed the case.