Alma, thought I would let you know that unless italki guidelines have been changed lately, giving free trial lessons or any free lesson of any kind on italki isn’t really allowed.
I don’t think italki booking system would even give you the option to set the price for less than $ 1/ trial lesson or less than $ 8/ lesson ($ 8 is the minimum price a professional teacher could offer on italki).
Also, I have a feeling that I read it some where on italki that advertising free lessons could get you in trouble, as in losing your teaching profile 😅
Again, this is how it used to be but maybe things have changed lately. You could try to set the price of trial lessons to 0 and see for yourself if it’s going to work or not.
Good luck 🍀