they replaced my battery with a smaller one

i bought a very beautiful renault Sandero stepway from renault, motus select in centurion, Jackson was my sales person, good guy. still helps me to this day. he then left for greener pastures and things have gone south since... my battery started giving me problems and like everyone else i went to a battery shop, they tested it and found that it was finished and i needed a new one in just one year of purchace. i was informed that the battery they put in my car is too small for the car and when i called Byron the manager to find our why they put a MUCH smaller battery he blue ticks me. - the battery of this car is a 652 if i am not mistaken, they put 612 in that car, i found myself having to cough out an unexpected R1500 a car battery should go on for atleast 2 years. another problem is that they gave me a car without its specific locknut so i struggle to change my tires and when i called i was told to come get it myself... unpleasant and not very honest these ones.