How to return unity back to its normal time scale and fixedDeltaTime

I used Time.timeScale = 0.02f; in my script without using the Time.fixedDeltaTime;( I did not know about it, I still don't would app. if someone could explain why we need to use it)

The problem I am facing now is that previously the places where I used AddForce(0,500,100) gave me decent results, now the rigidbody barely jumps when that code is activated. Is there a way to revert this back and what is the safe way to use Time.timeScale ?

PS : The AddForce is called under the FixedUpdate section.