Exercise $20-21($Algo$)$ Error in amortization schedule $[$LO$20-6]$

Wilkins Food Products Inc. acquired a packaging machine from Lawrence Specialists Corporation. Lawrence completed construction of the machine on January $1,2019.$ In payment for the machine Wilkins issued a three$-$year installment note to be paid in three equal payments at the end of each year. The payments include interest at the rate of $12\%.$ Lawrence made a conceptual error in preparing the amortization schedule, which Wilkins failed to discover until $2021.$ As a result of the error, Wilkins understated interest expense by $$59,000$ in $2019$ and $$54,000$ in $2020.$

Required:

$1.$ Indicate in the table below which accounts are incorrect as a result of these errors at January $1,2021$ and whether those accounts are understated or overstated. $($Ignore income taxes.$)$

$2.$ Prepare a journal entry to correct the error.

$3.$ Will Wilkins account for the error $($a$)$ retrospectively or $($b$)$ prospectively?