How do I recover missing notes from 2024-2025 in the Notes app on iPhone?

All my notes are saved through the Gmail part of the notes app, they’re not on Icloud, I checked. A few days ago something like this happened, the number of notes was down to like 24 and all my recent notes were gone. Then, I just had to close the app and open it again and they came back. Now all my notes from 2024-2025 have disappeared, except for one that was last edited two days ago. It was saying I had 84 notes two seconds ago, with all the notes missing, and I tried closing and reopening the app, and restarting my phone, toggling some settings in the settings app, and now it says I have 83, and all the notes from the last two years are still missing! The fact that they came back last time gives me the impression the files are still probably stored on my device or account somewhere, they’re just not showing up. They also aren’t showing up in my Gmail app, even when I searched specifically for notes from the past two years.

I think I saw the notes app updated a couple weeks or days ago? I don’t recall updating my phone or accepting any new terms of service recently, and I haven’t done anything to or with my google account.

[Re-Titled by Moderator]