Any nominators who used the form before Thursday June27 will need to resubmit their nomination.
Although the online form is the least-used channel for making a nomination, with 80 per cent of nominations coming via email or hard copy in 2018, the deadline is being extended to provide an opportunity for resubmission.
Nominations can now be submitted until Sunday July 14. The date of the awards ceremony will also be rescheduled.
The council says it regrets the fault and apologises for any inconvenience caused.
Events manager Tracey Wood encourages those who had submitted online nominations to do so again.
"We want to ensure the community minded citizens who had been nominated have their contributions to our city appraised by the evaluation committee," says Ms Wood.
"We also hope people who had been considering nominating a local hero take advantage of the extended nomination period."
Nominators who submitted the form before June 27 can send their nomination information to cityevents@hcc.govt.nz and council staff will complete the form on their behalf.
You can also collect a hard copy from the Council's Customer Services team on the ground floor of the Municipal Building in Garden Place.