I answered "Jsme hezcí" and it was wrong. Is there a reason why the pronoun "my" should be included in this situation? Since in this case we are not making a comparison like "we are this and you are that".
It is accepted, probably the same Duolingo bug as in your last report. Please do not hesitate to use "My answer should be accepted..."
Why is this "hezké"? I see no specific information about adjectives on the "Tips and notes" section of the Plural skill.