An Aucklander has yet to claim the $7.2m they won in the Powerball draw last Wednesday.
They purchased their ticket at Pak N Save in the northern suburb of Silverdale but, five days on, Lotto NZ says the winner has still not claimed their prize.
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"While the majority of Powerball winners are quick to claim their winnings, it's possible that New Zealand's latest multi-millionaire has no idea they've hit the jackpot," said Lotto NZ head of corporate communications Kirsten Robinson.
Lotto says tickets have been known to show up in odd places including in underwear drawers, backpacks, desks at work, in the car and inside phone cases.
In 2017 a $19.1m dollar prize winner from Warkworth found his ticket stashed in the car, and was unaware that it was the winning ticket until he popped into the supermarket.
"If I had known, I probably wouldn't have driven around all weekend with a very valuable ticket under my seat," he told Lotto NZ.
It's also common for people to hide their tickets in a 'safe' place and then forget where that was.
"We're encouraging anyone who bought their ticket from Pak N Save Silverdale recently to do a bit of spring clean - clear those wallets, clean out your kitchen drawers and rummage through the glovebox. You never know, that little yellow piece of paper tucked away somewhere special, could be worth $7.2 million," Ms Robinson said.
The winner has 12 months from the date of the draw in which to claim their prize.