The G7 Hiroshima Summit will begin on the 19th of this month. As a counter-terrorism measure, coin lockers and trash cans are no longer available at stations and airports in urban areas far from Hiroshima.
Some travelers are confused because they can't leave their luggage. The impact is widespread, so gather information in advance so you don't get in trouble. The last time a suitcase was found in front of a closed locker at JR Shibuya Station, the owner had an errand nearby and left it.