Torch/Flashlight turns off by itself, automatically when iPhone 12/13 mini and iPhone 13 display turns off

Hi, I had an iPhone 12 mini with this issue. I updated software, tried resetting and all that, but eventually I took it to the store I purchase, verified with the Apple Store, and managed to get a refund for it.

I bought the iPhone 13 mini yesterday, and it was a nice upgrade, but I noticed the same issue; I'm pretty sure I didn't restore from a backup but I can't really remember since I tried restoring like 5 times through my iTunes/Finder backup of my iPhone 12 mini but it wasn't working. I might have done the iPhone to iPhone transfer from a 1st gen iPhone SE to the iPhone 13 mini but I really don't think so.

Anyway, so I noticed the same torch turning off issue on the iPhone 13 mini when the display turns off (I notice it happens more frequently if Siri has been activated before using the torch) It's very similar, if not the same as this issue: https://discussions.apple.com/thread/253038733

My brother has a regular iPhone 13 and my mum has a 13 Pro Max, so I tried it on their phones but couldn't replicate the issue after trying dozens of times on each phone.

I tried swapping phones with my brother, and I did restore from my Mac backup, then now I found the same torch issue to be occurring on the iPhone 13 and now it's not happening on the iPhone 13 mini now that my brother is using it...

I'm really not sure what this issue is; I've tried googling it, playing around with software and accessibility settings, but I can't tell how to fix it.

What I'm going to try now is switching back to the iPhone 13 Mini without restoring from backup, and hopefully that sorts out the issue.

If that doesn't work, I'll try using a different or new Apple ID to see if that helps, otherwise I have no clue. I really like the Mini size and would hate to have to return this phone,