Google Assistant/Alexa open a gate with a pin code voice

Hi, I have a Sonoff T1 (using HACS: Sonoff Lan) doing the job of a gate switch, when the T1 goes from OFF to ON the switch waits one second and returns to OFF state, but for a matter of safety I have to enter a pin code to unlock the card (HACS: love lock card).

I want to use the Google Assistant on my phone or my Echo Dot 3 in order to open the door but using a pin code voice or something to do it. If you know something about this, it would be very helpful.

Thanks a lot!