Deferrals withheld on def of compensation

[Spencer]

Client has 403(b) plan. Plan doc says defintion of comp includes deferrals. Payroll company deducted cafeteria plan deductions and then calcuated 401k deferrals on that compensation (comp less cafeteria plan deductions).

To correct, employer needs calculate difference and make up deferrals plus lost earnings. And correct match as well. Right?

Thanks!