Anyone know why this rune is bugged?

hey

Most likely quest reward : https://wiki.guildwars.com/wiki/Missing_Shipment

• The Rune of Minor Vigor that this quest rewards may only be sold once per account. Once any of your characters have sold it to a rune trader, other characters cannot sell the quest reward rune to a rune trader. However, this seems to reset if you delete the character that sold the rune originally.