I’m hearing “me-a-e” and not “me-ae”, where “ae” is a diphthong. I reported the audio as wrong.
Ugh, I translated as if the patellae were nominative and therefore the subject of placent, and as if tibi were dative with the verb. So, I didn't use the English idiom preferred by Duolingo, but ... "Do my dishes please you?" would seem to carry the sense of the Latin.
I tried it again, a week later--because it seems natural enough to me--but it's still not accepted.