My new job misled me about the duties and changed their mind from a full time contract to casual and I'm not the only one

Hi there, Location: NSW, Australia

I started a new job over a month ago which was advertised as being a full time dispatch assistant role, listing the daily operations as pick packing orders, maintaining stock, cleaning the warehouse etc etc. During the interview they again said full time work as a dispatch assistant with "occassional" production line work. (placing satchets of powder into a box - producing around 500 boxes per person per day) When I was officially offered the job over the phone they said that due to their needs they are changing the role to casual with the option of reevaluation after roughly 6 weeks to go full time. I accepted and signed the contract. My first day should have been a red flag. I was in the production room the entire day packing these boxes of product alongside the actual production team (which I've seen found out are paid more) Since then I have spent nearly every single shift in the room packing these boxes. I've yet to actually pack customer orders at all, and I've done picking of orders maybe 6 times (not all day mind you) It's been 5 weeks. There were I think 4-5 other girls also hired by the same job ad, and nearly all of them have also been dumped into the production room with me. And more interesting, they all applied for full time work, but were offered casual at the end. They came before and after me so the hirers definitely knew they only wanted casual with me and the girls that came after.

I feel extremely lied to, and I gave up a part time job with good benefits to come to this job. Additionally the packing stations are very short and as a tall person I have been in extreme agony every day since I started, which I have brought up multiple times and have been dismissed on. Also they have done extremely illegal things with safety and forklifts which is something of another matter.

Would I have a case on fraudulent job descriptions or similar against them? I'm applying for other jobs but unfortunately I cannot just quit and leave on the spot due to financial limitations.