help on this question

the sales revenue in a company was $2 million and its receivable were 5% of sales.
The company wishes to have an allowance for receivable of 4% of receivable,which would make the allowance one-third higher than the current allowance.
how will the profit be affected by the change in allowance?
A)profit will be reduced by $1000
B)profit will be increase by $1000
C)profit will be reduced by $1333
D)profit will be increase by $1333

$2 million*5%=$100,000
allowance=4%*100,000=4000
1/3 higher than current allowance
1/3*4000=1333

my answer is C but the answer sheet is A

why how to get 1000? which part i calculation wrongly?

please help me thanks