Don't push personality

There are many ways to make characters realistic.

You want to give them tics. You want to give them flaws. You want to let them make mistakes.

These are all important things.

However, you can't force these traits.

You can't randomly add a car accident in your story to show that your protagonist is a bad driver. You can't make your character go to a coffee shop without advancing the story just to show how impatient they are.

Showing your character's humanity is important, but you have to do it in a way that fits with your story and advances your plot. Be patient; you'll find those perfect spots.