Query Regarding Different Shipping Rates for Same Location

Hello

I Just added 15 qty of “https://purelightcandles.com/product/serenity/” ftrom two different users but enter same address but the showing different shipping rates and TAX is also showing for one user. so can you please check let me know why its happening?

For one user shipping rate is:

Shipping:$99.66?via Priority Mail
Tax: 0

For second user Shipping rate is:
Priority Mail Express: $81.65
Priority Mail: $26.25
Tax: $24.76

Thanks
Hyper Effects

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