voltage limiter problem

i using two zener diode having 5V breakdown voltage as a limiter

two zener diode is parallel with each other but the one of the zener diode polarity is inverse.

if i connect to the input AC voltage, its should limit the voltage to 5V if the input is exceed 5 voltage.

i simulate it in the Multisim, but the output always same with the input no matter the input value is exceed or lower the breakdown voltage.

why this happen?

Multisim has many problems. You found one.

The zener resistance breaks down. You need fixed resistors in series to create a voltage divider.