Harassment from a seller?

Hey all,
Not sure if this counts as harassment yet, but I’m pretty on edge about a seller’s behavior and could use some advice.
I’m newer to Poshmark (but have used Depop before) and bought a transitional swaddle for my infant at the seller’s asking price for $20. I chose this seller because their profile said they typically ship same day.

After 6 days with no shipping update (still “order placed”), I sent a short, polite message asking for a timeline. No response, even though they were active. Later that day, I asked if they could cancel the order since Poshmark doesn’t let buyers cancel right away.

That’s when things escalated. The seller responded by calling me rude and went straight to name-calling, which felt really extreme given the situation. They refused to cancel and said I could do it myself after 7 days.

At that point, I reached out to customer service. Looping them in seemed to make the seller more aggressive, they started messaging in all caps, saying I was “demanding to cancel” and sending too many messages (I had sent 3 total, two asking to cancel). I stopped engaging and blocked them.
I contacted support again because I no longer felt comfortable receiving an item for my infant from this seller and the seller accessing my personal address 🙃, but they just told me to block and disengage and they didn’t cancel the order.

This morning (when I finally became eligible to cancel), the order suddenly showed as “shipped,” but there’s no tracking info. So now I’m stuck wondering if it was actually shipped or if they just marked it that way to prevent cancellation.
I’ve followed up with support again, but in the meantime, has anyone dealt with something like this? Any tips for getting Poshmark to step in more proactively or how to handle this if the item does show up?

Honestly a bit shaken that this escalated so fast over a $20 purchase.