Both errors are builtin features of the MacOS/iOS editor. if you type
Code:
12345spacespace

Two things happen — and both are intentional.
  1. the space space is see as end of sentence which automatically becomes period space
  2. 12345 is recognized as a decimal number and the comma separator is automatically added.

The same thing happens in almost every application in both MacOS and iOS whether it is from Apple or any other developer. I suspect your attribution of this as a Notes fault is a not unreasonable mis-interpretation of circumstances.

On MacOS this actions can be prevented in System Preferences > Text and Uncheck "Add period after a double space" and in System Preferences > Advanced > Languages & Region set Numbers Separator to "None". NOTE: this will effect virtually all applications on the system, or at least all those that use the Apple editor API.

In iOS look in Settings > General Keyboards and turn off "." shortcut. I can't locate where to turn off the numeric separator at the moment but you might try disabling spell checking altogether. Hopefully I will eventually dig up the proper switch or someone else will chime in with it.

SUGGESTION:
As I am pushing 80 my fingers are not as limber as they used to be and at times are subject to being a bit shaky whether I want to admit it or not. That can sometimes present data entry issues on a screen as small as the one on my iPhone. So I have found dictation is a satisfactory substitute. Admittedly it took Siri and me a while to become accustomed to one another idiosyncrasies. In particular I had to learn not to allow my Texas drawl too much latitude when dictating and to make beginning and ending consonants harder rather than softer. But I can now dictate to my iPhone with a high level of confidence that Siri will accurately interpret what I say and write it down with more consistent spelling. I have also had to learn that when I am being long winded, to allow Siri the occasional pause to catch up. One final caveat: NEVER EVER hit send until you have carefully proofread every word. Mistakes are few but often spectacular!

Last edited by joemikeb; 01/02/19 11:36 PM. Reason: boo boo and I typed this myself :(

If we knew what it was we were doing, it wouldn't be called research, would it?

— Albert Einstein