I delivered the Lunar Piece to Richard in Aqua Road and he gave me a letter to be delivered to his wife back in Amoria, but there's no way to give it to her. Talking to her yields no results.
Far as I am seeing you did not accept the quest given to you by Richard the Sailor after you turned in that one, you should not have any problems. We can probably improve how this part is handled to make it bit more clear, so I will leave the report open.
The letter should be given only once you start his quest, it shouldn't be a reward for turning the first quest in.
So after delivering the Lunar Piece to Richard, he gives me a time sensitive quest to deliver the letter to his wife back in Amoria. That is all the quest says as far as information. To be fair, I didn't realize it was time sensitive at first and the letter expired and disappeared from my inventory. I had to forfeit the quest and start over, delivering the lunar piece again and this time I headed straight back to Amoria and was met with my screenshot from above.
Thank you for answering! Is it possible for it to not show up on “Available Quest” tab, like the other repeatable quests? https://royals.ms/forum/threads/cupids-courier-feedback.191911/