I have found out what caused this for me. Apparently I have missed to open the reward chest for the Grove. Once I went there it popped up, along with the world completion reward.
I have completed the world, but have not received the two Gifts of Exploration.
I have gotten the normal region completion award (2 pieces of equipment, 3 transmutation stones, bunch of crafting materials) as well as the title, but the Gifts of Exploration (which are the reason I did the world completion) are missing.
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