How often have I heard this “reason” for something that is in someone’s writing or signature!
“I write this way because it’s the way I was taught at school” is the commonest.
OK, so when were you at school?
If your teacher stopped smacking your knuckles with a ruler when you put the wrong size of loop on your “j” or made your capitals too large, last week, then I agree: you are doing it because your teacher said so.
But if it is several, or even many years since you stopped being under the influence of Miss StrictTeacher, then it’s also time to stop blaming her for how you write!!
Do you write every single stroke exactly the way your teacher showed you?
Of course you don’t. You’ve chosen some to leave as is, and some to change.
If you have indeed retained any of the strokes exactly as she showed you, it’s because these strokes are a fit for your personality. Otherwise you would have changed them.
So don’t blame your teacher.
Instead, take the time to find out what your signature says about you, and then change anything you don’t like into something that says what you want it to say about you.
Handwriting is body language. Change your body language over a period of time and you will change the personality trait associated with it.