The general university canteen belongs to the administrative department of the school. You can complain to the school first. If the school doesn't handle it, you can complain to the Education Bureau or the Price Bureau.
If you have any comments, you can ask the boss directly, or through the Youth League Committee and the Student Union!
In view of the management of students' meals in the compulsory stage, the education department has issued relevant notices, stipulating that schools must carefully review the contents of student subsidies and the supervision of canteen management, and may not contract or entrust others to operate.