Question

I am trying to calculate the cost of debt for a company. I found the weighted average interest rate for all its outstanding debt, and found amount of interest the company should be paying on that debt. However, the amount of interest I calculated is not the same as the interest expense on the company's financials. As a disclaimer, I remembered to calculate the interest expense as after tax cost of debt. So finally, my question is, should I be using the interest expense on the financials or my calculated interest expense. Thanks in advance.