Notes from apple notes app vanished

About two years back some of my very important notes in my apple notes app went missing. While inspecting it out, I realized it's because I accidentally used to write my notes on the iCloud section when I didn't have enough space in my Cloud. I had shifted from the settings to use only the On My iPad option instead of iCloud and I didn't realize at that time that it would make some of the notes that were saved in my iCloud section go missing. Not all of my notes were deleted but – I assume – only the ones that didn't get saved in the Cloud (due to the lack of iCloud storage space) were missing.

Is there a way to retrieve those missing notes? I'm still using the same iPad. I even held out updating for over a year hoping that I could find a way to retrieve them, I was worried that updating the software would delete those files if they were still in there somewhere however eventually I did update to iPadOS 16. I tried many things to try and retrieve the files such using Mac apps to search through iPadOS system folders and such. Nothing worked so far. I really need notes now, they are quite important for my work and studies: loosing them forever would be a big blow to me.

I wanted to reach out to the community many times before but this the first time I'm doing it because I am in a desperate position right now. Many thanks in advance for the people who took their time to read through this and help me.