BALTIMORE (AP) — The relaunch of speed cameras in a Maryland city has stumbled after the program’s vendor issued nearly $39,000 in duplicate tickets on its first day.

News outlets report the 962 people who received the duplicate tickets on July 31 will receive a letter explaining the error and have their violations forgiven, while drivers in Baltimore who only received one ticket must pay their fines.

American Traffic Solutions spokesman Charles Territo says the company added a manual review to its automated process as an additional quality check to the first round of violations, but the violation file was submitted twice, causing the error.

Transportation Director Michelle Pourciau says unlike past problems with the system, the extra tickets were the result of the vendor’s error and not a problem with the cameras.