The AI answer to this question came up as wrong,

Problem $4-31$ Calculating Interest Expense

You receive a credit card application from Shady Banks Savings and Loan offering an introductory rate of $2\mathrm{.}3$ percent per year, compounded monthly for the first six months, increasing thereafter to $18$ percent compounded monthly. Assuming you transfer the $$8,100$ balance from your existing credit card and make no subsequent payments, how much interest will you owe at the end of the first year? $($Do not round intermediate calculations and round your answer to $2$ decimal places, e$.$g$.,32\mathrm{.}16.)$

Answer is complete but not entirely correct.

$\backslash$table$[[$Interest accrued,$$8,199\mathrm{.}92$xan expert explain this?