Can't Repeat Quest Sacred Cloth for Mooncloth Boots Tailoring Pattern

If you completed Sacred Cloth, then abandoned tailoring and learned tailoring again, you won't be able to repeat the quest to obtain the Mooncloth Boots pattern again.

If you chose to abandon tailoring in WoW Classic, your choice comes with all the consequences and is not possible to re-obtain patterns that were quest rewards. If you are experiencing this issue in Shadowlands, the Game Masters can make an exception and help.