A method, comprising : - providing a combination (LC1) of a package (200) and a label (100) attached to the package (200), wherein the label (100) comprises a fluorescent substance, - illuminating the label (100) with excitation light (EX1) so as to cause the label (100) to emit fluorescence light (LUM1), - capturing an image (IMG1) of the label (100) by using an imaging unit (CAM1), and - detecting the position of the label (100) by analyzing the captured image (IMG1) and/or detecting a degree of adhesion of the label (100) by analyzing the captured image (IMG1).