StackOverflow error thrown on Invoices toString()

[jawad-r3]

Method threw 'java.lang.StackOverflowError' exception. Cannot evaluate com.xero.models.accounting.Invoices.toString()

@OverRide
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append("class Invoices {\n");
sb.append(" invoices: ").append(toIndentedString(invoices)).append("\n");
sb.append("}");
return sb.toString();
}

/**

• Convert the given object to string with each line indented by 4 spaces (except the first line).
  */
  private String toIndentedString(java.lang.Object o) {
  if (o == null) {
  return "null";
  }
  return o.toString().replace("\n", "\n ");
  }