Bad salesman

I recently bought a mercedes from sa motorcorp. The salesman told me there’s a spare key from the first day. I bought the car and paid in full since there wasn’t a willingness to discount at all. When the payement was done the salesman brought 2 keys. One was not for the car. When i approached the manager he passed the buck to the salesman. I left unsatisfied and had to bear the cost of a new key myself. Out of goodwill i did not make an issue out of. 10 days later i went to register the car but the paperwork was incomplete and when i called i just heard lame excuses. I will never go back to them after this poor salesmanship and non accountability