I have had 3 hens that "crowed". Typically it was just a few times in the morning. One of them was too aggressive and crazy (I learned that Blue Andalusians are not good backyard city chickens) and she was relocated moved to the country. The other two eventually stopped. No guarantee yours will stop too (if it is indeed a hen), but if it is only once a day is it that big of a deal? The egg songs from my others are as loud as the hen crowing, and goes on longer, so the hen crowing never bothered me much (although I did lock them in until 8 am sometimes when I want to wake up so it didn't happen at sunrise).
Colleen
Colleen