The recently-announced Mew serial code distribution event began for Pokémon Sun and Moon players in Japan earlier today, July 11. Because the event had the OT ２０ＴＨ☆, this caused a glitch to happen should the event be traded through any means. Due to the ☆, it would cause the OT to reset to Sun., Sonne., サン., Soleil., Sol., Sole. & 썬 depending on the language of the game. However, you can rest assured that the event has now been rectified, removing the star leaving the OT as ２０ＴＨ.
Source: Serebii
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