I recall the land purchase thing and that that there were issues with the loan. It sucks and sometimes the timing of things is diabolical, clearly in your case it is. (Covid etc.)
Here in Adelaide things are selling well, good prices and reasonably quickly. I was under the impression that was the case elsewhere but clearly in Melbourne it's not. I guess the negativity of the second lockdown and the ramifications of it have dented confidence. I'm in the industry here but that doesn't mean I know about other States and so I could be wrong. Just surmising.
All I can say is to ask the sales agent for recent sales data of similar properties in and around your suburb. RPdata (core logic) will be able to demonstrate what's sold recently, last three months, and that's what's most relevant. It seems you're not asking an exorbitant price but the market dictates and with little or no action on yours there's a reason why. It is important to know that reason as it may be something you can work around. Your agent should be doing this stuff, not just sitting back...They need to be proactive.
The market is always going to lowball, it's what they do, and then the agent negotiates. The problem comes when no one is there to offer. I don't know the situation but try something different: Change the photos order on realestate.com.au, change the text and give it a new look. Change the price too...For instance, if you're asking $440,000 flat make it $439,950-$449,950 or some such thing...A little bit over and little but under what you really want. It shows movement, that you're willing to work with the market, and may draw in buyers. That, with a refresh on the appearance, may help.
Remember, the marketing price is about drawing people there, that's all. The selling price is negotiable but the sales person needs someone there to negotiate with to get the ball rolling. I'd never ask a person to change their acceptance price, just the marketing price.
It's difficult for me to say (help) much without knowing all the ins a s outs of it, but have a think about the above, if you haven't already.
Good luck and all the best.