Boss left me as sole employee halfway through an 8-Hour shift on ‘trial’ first day, says it is an unpaid shift regardless.

Hey All, I just started a new job today under a temp contract placement to be a pop-up kiosk salesman in a shopping centre, selling aircon and other shit, just a job to bounce between cause getting hired with little/no experience is stupid difficult

I’m in Ballarat, and my two bosses came down from Melbourne to setup this venue; and I’m employed 9-5 Tuesday-Sunday this week, it was originally gonna be Mon-Sun for this week and next week, but they told me yesterday on my first shift that it would only be one week

That’s not the problem though, simple thing is that they quite literally left not even halfway through my first ‘trial’ shift
Worst yet, they’re saying that due to it being a ‘trial shift’ (careful to not say training on their part), that it qualifies as an unpaid day. Is this correct? I thought that was only a viable thing if it is genuinely a training day, with proper mentoring.

An itinerary of the day went something like this; * 9:00 - Arrive at work to begin shift. * 9:20 - The two bosses arrive to set up the stall * 9:30 - I’m shown two apps I need to download on my phone (Runabout and WhatsApp) and verbally instructed on the processes of making a sale. * 9:40 - Handed uniform to change into, and they leave to do something I’m not sure. * 10:30 - The second of the two bosses comes back for a 3 minute checkup and to tell me to “try and grab customers attention” * 10:33* - That boss also leaves and the two of them head back to Melbourne * 10:30 - 17:00, I’m working completely on my own, including closing and sales and everything.

For the remaining 6.5 hours of my shift, I am completely on my own, this is the first ever sales job I’ve done (I’m 19), and at the end of the day I had to close up and head home When I asked them specifically about today, they said that due to being a trial day, I would not receive a salary. This was not a trial shift though was it??? And I was not aware that they would be departing, and I am the only one assigned to Ballarat, so I’m the only employee. I do have contact to a team through WhatsApp, but that’s besides the point. I had to contact them probably 4-5 times to make sure what the actual process was, because they completely forgot an entire part of the process for doing specific products.

Can anyone offer me any advice on what to do? I really need yesterday’s money as well, and I feel like that counts as a situation where I’m working essentially as an employed employee, not a trainee The company is pretty sketchy overall, getting my bank credentials at the end of the employment to pay me, and whatnot My hours are tracked, both in their little company, as well as what I’m doing personally

I don’t really wanna quit, as it’s just for a week and I very desperately need money to make rent and also help my GF get on her feet as she’s struggling to make ends meet. It’s $150 per day, plus a $20 commission per thing I can sell. So not the best, but not the worst either

Thank you my mateys

Edit: Thank you all for your comments, I apologise if this post was kinda low quality or written poorly I took all of yours’ advice and quit, I decided to sent them a proper message explaining my concerns and stance and that I will remain firm in my decision

They tried to call me back twice, and then a third time on a different number I decided to answer and it was a different department who I heard out but decided to decline still (Hearing people out is my weakness)

They said they’ll have a written contract in by Friday for “transparency for you”, and also that “We’ll extend it to yesterday as well” and then they also finally asked for my credentials as well, which when I said that even though I wish them best, they can shove it, and I hung up.