Notes disappeared on my ipad

I have notes on all my devices but just now the notes disappeared from my ipad. It’s the notepad app. Thankfully theyre still on my mac and iphone. I googled it and even asked my sister.

this was basically the answer i got.

I updated my iphone to 18.1 when i5 prompted me. so did my mac. But my ipad is stuck on 16.7.10 it never got a prompt. (I assume my Mac is 18.1 not too sure.) the thing is my ipad i got September 2019. I guess it’s too old or outdated? Also my notes are in my Icloud too.