This clinic is unable to issue COVID-19 test certificates unfortunately.
If you need to have a test certificate to travel abroad, we suggest you contact TeCOT (COVID-19 Testing Centre for Overseas Travelers). TeCOT is a governmental body which specializes in advising COVID-19 related matters including information on COVID-19 test conducting medical institutions throughout Japan.
TeCOT call center (service hours: from 9:00 to 17:00):
Phone: 0570-039656 (for IP phone users: 03-6830-8027)
TeCOT Website: https://www.meti.go.jp/english/policy/trade_and_invest/tecot/index.html