SPCA sold our puppy without our permission

I went to spca Sandton because my puppy was not well and i thout is sheap compare to animal private hospital. First we pay R400 + they gave puppy some medication and advise us if the dog does recover we must return him and after 3 days we went back because my puppy was still not well .they told us to pay the admition fee because they going to admitt the puppy and they told us they will change R1500 .and we told them that we don't have now and we are taking him back home they said by law animals when they are sick they don't give people to return back with them.and said to us we must leave they will call us when the dog is fine .but they didn't,after some times we went there with that R1500 to take our puppy back we found out that our puppy is no more they sold it without our permission not even a call from them or sms saying we must come and collect our puppy .they just told us they come to our home to report it but they didn't get anyone there and when we ask about our money that we 've already spent there for our puppy they said it was our responsibility to do so and they didn't even gave us onother puppy .