Updated: 6/4 9:50 PM (UTC-8)
Earlier today, we had confirmed the issue detailed down below.
The issue has since been addressed and the first-time clear rewards have been successfully distributed to the players who have cleared Multiplayer! Annihilation Descended Rush! but did not receive the rewards.
We sincerely apologize for the inconvenience, and thank you for your patience and understanding.
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An issue was confirmed with the Multiplayer! Annihilation Descended Rush!, a part of the current PAD Best Friends Event.
We have confirmed that some players who have successfully cleared Multiplayer! Annihilation Descended Rush! have not received their special first-time clear rewards. The issue has since been addressed and the rewards are being delivered correctly.
To see more details on the PAD Best Friends Event, see here: https://bit.ly/2ZP7PPJ
We sincerely apologize for this inconvenience and thank you for your understanding.