vodacom cant replace my tablet.

Hey I took a voda tablet contract with vodacom & now is no longer charging I took it for repairs & they phoned me saying I must come collect it & when Igot there they told me that its not fixable & they would change it if it didn't have a damage on the cover which I don't know of & again I ddon't understand how come they can'treplace it coz what they saying its unfixable. Now I'm paying for something that I don't have.