Extract_slot1_name gets called for both slot1_name and slot2_name

I have a custom action for my form, that has extract functions like this :

Slots : test_cuisine, test_num_people, test_buffet

Whenever a slot is filled, all these three extract functions get triggered. Ideally while filling test_cuisine only extract_test_cuisine should get filled, right ?

Is there some mistake in the action code that I’ve written ? Any help is appreciated!