Excel Calculation of Before and After Cost of debt

Bond is redeemable at premium 5% of the 1000 face value i.e 1050.

I J I and J are cell name.
Tax Rate 35%
Coupon Rate 15%
Maturity Value 1050
Face Value 1000
No of Years of Bond 7
Present Value 976
Brfore Tax Cost of Debt 16.03%
After Tax Cost of Debt Missing % Here i have problem

It should be 10.8%.

I need after cost of debt 10.8% but its not coming

Remember: Bond is redeemable at premium 5% of the 1000 face value i.e 1050.


Thanks in advance.