Is there a place where I can consult about contract problems etc. on Saturdays and Sundays?

The following consumer consultation counters are open on Saturdays and Sundays.

consumer hotline
If the city or metropolitan consumer affairs centers are closed on Saturdays, Sundays, and holidays, calls will be made to the National Consumer Affairs Center of Japan. (10:00 a.m. to 4:00 p.m., year-end and New Year holidays, excluding National Consumer Affairs Center building inspection days)
Phone number 188 (no area code)

Tokyo Metropolitan Consumer Affairs Center
Opening day Saturday Phone number 03-3235-1155
Reception hours: 9:00 a.m. to 5:00 p.m. (excluding holidays and New Year's holidays)
　
National Association of Consumer Affairs Counselors (Public Interest Incorporated Association)
Opening days Saturday and Sunday Phone number 03-5614-0189
Reception hours: 10 a.m. to noon, 1 p.m. to 4 p.m. (excluding year-end and New Year holidays)
　
Japan Association of Consumer Affairs Advisors, Consultants and Counselors, Public Interest Incorporated Association
Opening day Sunday Phone number 03-6450-6631
Reception hours: 11:00 a.m. to 4:00 p.m. (excluding year-end and New Year holidays)