NEW YORK (CBSNewYork) – It’s a story we’ve been following for months.

New York City parents remain infuriated over their inability to track their kids on city school buses.

Now they say a backup plan using the bus’ GPS system is also experiencing issues.

For Bunny Rivera, waiting for her son’s school bus is the most stressful part of the day. 13-year-old Chazz Rivera is on the autism spectrum and Rivera says she was depending on a new phone app to alert her of his location, but it never came.

“No one knows where their child is, and it’s terrifying. My child is somewhere in the city he special needs and I have no idea where he is,” Rivera told CBS2’s Christina Fan.

Councilmember Ben Kallos, who spearheaded the legislation, says it’s unacceptable.

“Pretty standard technology, and they had to get it done by the first day of school. I’m very disappointed it wasn’t done by the first day of school,” Kallos said.