iPhone photos not syncing with iCloud

My laptop & iPhone are both signed in under the same iCloud account. I'm trying to make space on my iPhone, so deleting lots of old photos. I'm doing the deletion from my laptop, since it's quicker/easier. I've dropped my photo library from 8,837 photos to 8,333. But this is ONLY the number I see on the laptop & iCloud.com. The iPhone isn't moving down from 8,837.

I've checked that I'm signed into the correct iCloud account. I'm not on Low Power Mode. I'm connected to power. What's left to try?

I saw some suggestions to (from my iPhone) go to My Name > iCloud > Photos > Toggle off iCloud Photos & Toggle back on again. But there's a missing step in that last part. When I toggle off iCloud Photos it says:

"Do you want to download a copy of your iCloud Photos to this iPhone? Photos and videos that have been optimized to save space will be removed from this iPhone. The original, full versions will still be available on other devices using iCloud Photos."

What would I select here? Neither option really makes sense, as I DO want to keep the existing photos on my phone (minus the ones I deleted), and I DON'T want to download a (new) copy.

Any ideas? Thanks!

Jesse