Media Queries not Working in Tailwind CSS

Media Queries in TailWind CSS are not working Well.

My Code is this

<img src={MYIMAGE} alt="Test Image" className="h-6 w-8 rounded-md gfold:h-8 gfold:w-14 gfold:rounded-xl sm:h-16 sm:w-24 " />

gfold -> (400px) - A Media Size included by me in the tailwind.config.js file.
sm -> (640px) - A Default Media Size that Comes with Tailwind.

When Media Size is below sm size is correct, But when my screen is greater than the sm size the Size is not Changing.

Now what should I do? Please help me, I am new to Tailwind CSS.