Fang Zhirong came across this signboard near Punggol (or is it Ponggol?) which showed two versions of the streetname.
He was puzzled enough to send this query in.
STOMP did a check, and dug up this Straits Times article on the spelling of the town name.
May 8, 2001
For instance, few in Punggol or Ponggol, as it is sometimes spelt, can recall the activity of "hurling sticks into trees to bring fruit down", that could have prompted the area's Malay name.
However, there is another possible meaning of the word - a "place where fruit and produce are offered wholesale."
It appears that both are correct.
Article and photo source: Stomp
▪ Punggol Etymology