"고기를 자르고 냉동고에 넣었어요."
Translation:He cut the meat and put it in the freezer.
The Korean sentence doesn't actually explicitly say "him." It doesn't state who the subject of the sentence is, so without context, it's pretty open to interpretation. The subject could just as easily be "you", "she", "I", etc. If it didn't accept your answer with a different subject, report the question so that they'll see it and fix it!