The Children's Minister was informed about serious concerns regarding Hyde and Seek Childcare more than a year ago.
Katherine Zappone was also told at the time that the centre wasn't registered with Tusla.
But the crèche in north Dublin continued to be unregistered for another seven months.
In August 2018, Finance Minister and Dublin Central TD Paschal Donohoe forwarded a copy of a complaint he had received from a constituent to Katherine Zappone.
The constituent was a parent of a child who attended the Hyde and Seek facility in Glasnevin.
They raised serious concerns about the facility, including how it wasn't registered with Tusla.
They also described the centre as 'absolutely disorganised' and raised fears about the turn-over in staff.
In March of this year, Minister Zappone wrote to Minister Donohoe to confirm the centre was registered with Tusla in March - 14 months after it began operating.
Fianna Fáil's spokesperson for children, Anne Rabbitte, obtained the documents under the Freedom of Information Act.
“For 14 months, this facility was allowed to provide care to children and pretend to parents that it was a properly registered, regulated service when it was in fact operating in the absence of any permission, Deputy Rabbitte said.
“I find it deeply disturbing to think that identification of childcare facilities breaching regulations is being left to concerned citizens, rather than the Minister and Department."
In July, an RTÉ Investigates documentary revealed concerning practices at Hyde and Seek's crèches.