It is not just you. I can use Grammarly to correct/scan for grammatical/syntax errors. I can read them over and over and over...and I will still miss one.

It still happens. I have reduced the errors by writing in chapters, then editing multiple times, then compiling the whole work, then....yeah, you guessed it...I edit it again...twice.

I have reduced the number of errors significantly, but the mind plays tricks because we know what we want to say...and we read it that way...even when it is wrong...

Good luck friend!

Worse still is when you write something and realize "oh I know how to say this a better way" change it not realizing it now totally messes with everything else lol.
Glad I'm not the only one.