Dried out glue

i went to dis-chem in our mall in welkom in the freestate and bought Kiss 100 nails and when i got home and wanted to do my nails the glue was dry. the next day i went to return it and the cosmetic lady swopped it and told me this one is better and ensured me that the glue is still fine..... but that afternoon when i tried to apply it i soon realized the glue was dried out.... why are they selling products that is not right, in todays life we don't have a lot of money just to throw around and i wanted to really treat myself a bit