From the official site.
https://www.toei.co.jp/company/press/1217821_2819.html

About some reports about Tokyo studio
In response to the positive result of the new coronavirus by the performers of the television work, some news was reported on March 31 that "the studio was closed", but the studio was not closed at all on the day, There is misinformation about the press. The shooting studio is taking measures in consultation with the health center and further strengthening precautionary measures, and is still operating normally.