Frustration is building among locals in Finglas and Ballymun over issues with the 17A bus service.
The route runs from Blanchardstown to Kilbarrack, and is relied upon by the Ballymun and Finglas communities to get to Beaumont and Connolly Hospitals, and also to get to work and school.
But according to locals, the "shocking service" is repeatedly late or doesn't show up at all.
Users of the 17A - one of the services now operated by Go-Ahead Ireland - have also said that the Real Time Information monitors aren't updated to reflect if the service is late or cancelled, so there is uncertainty around when the bus will come.
Councillor Noeleen Reilly said she has been getting many complaints about the service since October but it has gotten worse in recent weeks.
She told Dublin Live that the service is "not good enough" and is "failing" the communities in Ballymun and Finglas.
She said: "There's always been issues with the route. It's such a long route and it goes quite a journey and it's not always as frequent as it should be.
"There's a couple of things here that are going on. Trips are being cancelled and the Real Time monitors aren't being updated and also they're turning up late.
"People are just showing up not knowing if the bus is going to show up.
"There would also be a lot of people in the Ballymun and Finglas communities that work out in Blanchardstown or would work in the Coolock in the Northside Shopping centre or in some of the industrial estates and obviously kids going to school.
"It's not like people are just squandering into town. They need the bus for a specific reason to get to work or school.
"One parent told me yesterday that her child has gotten two reports, and the next one she gets will be detention because she's turned up late to school twice in the last week, through no fault of her own because the bus was late or didn't turn up."
New BusConnects Oribital services, called the N4 and the N6, are due to be rolled out this summer and will replace the 17A.
A spokesperson for the National Transport Authority told Dublin Live: "The NTA is aware of recent issues on the route.
"On behalf of our customers, we have been working closely with the operator to address this and we expect reliability to improve steadily this week and over the coming weeks.”
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