Many texts did not transfer to new iPhone 17 Pro (Only 2025 Texts and Pre-2025 Attachments Are Showing)

I recently upgraded to a new iPhone 17. Both my old iPhone 12 and the new phone have Messages in iCloud turned on. iCloud says I have all ≈183,000 messages. I know that's a lot, so maybe that's why it is taking so long. My issue is that on my new iPhone, only attachments from old messages appear, not the text content. Basically, any chat sent or received prior to 2025 is not showing up—only attachments from texts before 2025. All messages from January 2025 to now do show up. Originally, my old iPhone 12 had all the text messages, but when it synced with iCloud yesterday, they seemed to disappear from that device too. My only hope is that iCloud does show the correct number of texts I should have, ≈183,000. I find it odd that when I try to toggle off Messages in iCloud settings, I get an alert that says, "Messages have not been fully downloaded to this iPhone," which makes me think that iCloud is still indexing to this new phone. It also simultaneously says that everything has been synced in iMessage. Anyone else have this issue?