GST(Tax) not calculated correctly | WordPress.org

hey,
we have just setup the site and while we have added the GST values and % correctly in the backend, it is not calculating it correctly. all the settings in the Tax tab is also setup properly.

The GST is 5% which is split between CGST(2.5%) and SGST(2.5%).
but during checkout it is calculating approx 4.7% for some reason.

I am using Standard Shipping rates.

please help in this

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