The Super Sentai actress suffered an acute allergic reaction.
It was announced on April 11 that Arisa Komiya would be going on a brief hiatus due to a sudden allergic reaction.
Arisa Komiya is most known by tokusatsu fans as Go-Buster Yellow in Tokumei Sentai Gobusters. She is also known as Dia Kurosawa in the Love Live! Sunshine!! franchise and played Sara in Garo: Divine Flame.
After Komiya began showing symptoms, an allergy examination was performed and determined she suffered from severe hives due to an unknown acute allergy. She was advised to rest for two weeks in order to recover.
Because of this order, she will no longer perform several Love Live! Sunshine!! concerts on the 2019 tour and will also be absent for a completion screening of an upcoming live-action film, Toshimaen.
She is expected to make a full recovery.
Source: Anime News Network