Synchrony Financial Credit Card Complaint

Synchrony Financial Credit card department,

Late fee California

I was very busy with a sick child and went to pay my bill 5 days late today. When I got to Toys R us Credit CArd to paymy bill there was a $25.00 late charge on a $140.00 balance. Which is about 18 %? What are the rules for this percentage? I have not been late before and this appears to me to be excessive. - -