Hello.
Could you please define name:ja in addition to name:ja-hira and name:ja-Latn? I had fixed thier name the other day, but it seems to have been removed again. 
https://www.openstreetmap.org/relation/341906
https://www.openstreetmap.org/relation/358631
It appears that your edits do not include name:ja. Without it, depending on the user's PC environments,name:en may be prioritized, whichi could result in insufficient search results in Japanese. Thank you for your cooperation. 