Does the harmless error rule apply in this case?

There is a harmless error rule that may cause an offer of payment to appear relevant, but it does not apply in this case. The rule is as follows: If a borrower proves irregularities in the trustee's sale, the irregularities will be deemed harmless unless the borrower can prove s/he offered to redeem the property. (Lona v. Citibank (2011) 202 Cal.App.4th 89, 112.) In this case, the Poulsons have failed to properly allege facts that would show an irregularity in the sale. Therefore, a court would not reach the issue of whether payment was offered. As a result, we conclude the trial court did not err by sustaining the demurrer.