Every customer of a licensee shall, within thirty days after the close of each calendar month, account and pay to his, her, or its collection agency all sums owing to the collection agency for payments received by the customer during that calendar month on claims in the hands of the collection agency.

If a customer fails to pay a licensee any sums due under this section, the licensee shall, in addition to other remedies provided by law, have the right to offset any moneys due the licensee under this section against any moneys due customer under RCW 19.16.210.