Help! My Boss Wants Me To Return My Tips To Her. I’m A Barista

So this coffee shop I’ve worked at for 4 months has had a lot of sketchy things happen which have made me consider quitting. THIS situation might do it ????So for info, there is no clock in/clock out here. You’re scheduled for your shift and that’s what you get paid for. Doesn’t matter if you come in earlier and hop in or stay later to help your coworkers. You just get paid what you’re scheduled. So today my shift was 7-9:30am. The owner came in for her shift early and started working on stuff that I had out as more customers came in. Around 9:29/30 I was helping this group that came in, they took a while to order but I helped them, and then made all of their drinks. It was a good size order and they tipped $9. It is time stamped for 9:34. After that, I cashed out and took my card tips for the day which totaled $15. FIFTEEN DOLLARS. That $9 was more than half of what I would have got today.So imagine my surprise when she texts me asking for the $9 returned so she can have it for her shift??? She’s the owner and works most of the day (mid)! The opener (me) and closer only have 2.5 hour shifts. She gets a majority of the tips anyway because she works the busiest hours. Also I should say there hasn’t been a “last time” like she’s implying. She’s confusing me with someone else I’m pretty sure? This hasn’t happened to me before, and if it did, I’d be fighting to figure out what to do like I am now! This policy that she explains in the last text hasn’t been told to me before. I’ve definitely taken tips after my “shift end” if it was a customer who I helped on the register and made the drink myself. I live in WA state and I thought owners weren’t so supposed to take any tips. I don’t care but she’s trying to take mine so how should I proceed?? I don’t feel like giving it back and I’m considering quitting over this.

I can’t attach pics of our text but this is how it goes:

Boss: Hey so I was checking the tips from this morning and it looks like you claimed the tip after 9:30 again. Includes photo of transactions that shows the 9:34 timestamp for tip in question

Me: I only included that one because it was that group who I helped and made all the drinks for

Boss: Like I explained last time. The tips switch over at the next shift. I was making and cleaning up the breakfast sandwiches you had out and unfinished which I started over 10 minutes prior to my shift. I was working during my shift finishing that as well. It doesn't matter what it is you're specifically doing, tips goes to the next on shift at shift change because your shift is over.

I haven’t replied after that because I don’t know what to think but this just doesn’t seem right? I live in Washington State and Google says owners aren’t typically supposed to get tips but I don’t know much. What are my rights here when my scheduled shift ended at 9:30 but I stayed and the last group that tipped me is time stamped for 9:34? Again, there’s no clock in/ clock out that proves I stayed later or has my name attached to that transaction.

Any advice on how to respond and proceed would be greatly appreciated. I’m a 26f and new to Reddit. I was recommended to post here after posting on another social media platform