shipping methods

How to hide specific shipping methods when Free Shipping is available in WooCommerce

1) Free Shipping: If Minimum order amount is above $100
2) Normal Shipping (Flat Rate) – Amount $7.80
3) Express Shipping (Flat Rate) – Amount $25

I would like Express Shipping option to be always available (shown).

But when Free shipping is available (meaning that the customer has more than $100 in the cart) I would like to hide Normal Shipping only.

So when Free shipping is NOT available (and hidden), the available shipping rates will be Normal Shipping and Express Shipping.

Could you please help me!

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