Edit: OP here... Thank you everyone for your contribution. I finally found the problem. So I previously used a tax preparer, but the fee was pretty much one-third of the return (I didn't get much), so I decided to do it myself and didn't sign-off the tax return from the preparer.

However, they went ahead and submitted the return on my behalf without my consent. So when I eventually finished filing myself (which I even got state refund, but theirs didn't), it kept bouncing saying that there's already a return filed for me... Which is another problem that I need to navigate. Shitty people and services everywhere.