If you opt to hide the sold price on the portals, they may obtain this information through other avenues such as PropTrack, who obtain such information from a variety of sources, including the Valuer General and/or LANDATA (if you are located in Victoria).
Whilst we cannot confirm exactly where the sold price of your listing was pulled from, you may wish to contact the portal directly so they can let you know where the data was obtained from.
If the sold price of the property falls within the below categories, you may be eligible to have the price removed from public display:
If the property has not settled
Certain off-market sales, such as part sales, title transfers, and gifted property
If the information is proven to be incorrect
If the sale relates to a purchase of the company title rather than the purchase of a property title
You can read more information about sold price disclosure at this link here.
Alternatively, you may wish to reach out to your Account Manager at the portal in question.