If they are this worried about how their customers dress they should change from the name Carnival.
Carnival typically involves a public celebration or parade combining some elements of a circus, mask and public street party. People often dress up or masquerade during the celebrations.
Miscommunication? Misunderstanding? Really? Their first email was pretty clear.
I”m not convinced there was any misunderstanding , but I’m glad that Carnival has apologized, reversed its position about dressing up on this cruise and has offered full refunds including non-refundable travel expenses.