Amazon Prime Day Deal: TP-Link Smart Plug $19.99+tax (Possibly lower)

TP-Link Smart Plug is $19.99+tax for Prime Members. My total came out a bit different:
Item(s) Subtotal:$29.90
Shipping & Handling:$0.00
Prime Savings:-$9.91
Alexa:-$11.96
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Total before tax:$8.03
Estimated tax to be collected:$0.58
Gift Card Amount:-$8.61
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Grand Total:$0.00
https://www.amazon.com/TP-Link-Re…Smart+Plug