No shift for 3 weeks

Hi,

I work in a part time weekend job, it is a zero hour contract. Last week I did not have any shifts, this week I have not been given any shifts and next week I have not been given any shifts. That’s 3 weeks in total. I am aware it’s zero hours and they don’t have to give any. But other people have been getting two shifts per weekend or getting at least one shift every week. They have been getting one every week, where I have been getting none, Surley they should not have any one week and I get one instead. Because I have gone 3 weeks with no shifts when they have received one every week. Do you think this is fair and what should I do.