The Tria of Corruption quest chain item bug....

Have a nice day. To complete the quest The Tria of Corruption, I defeated the boss in the Titan grotto and received the flame ruby ​​item required for the quest. However, when I went to Zarka in the Ardura caravan to deliver the quest, I did not have the flame ruby ​​on me. I beat the boss a few more times, but this time he did not give me the flame ruby ​​item. I cannot continue the quest series. I would be happy if you help.