Glocell No sell

I am very disappointed in the service I received at the Cell C Store @ The Bridge. I have been given a Nokia 8 and wanted to put new SIM card into phone. I was informed that I cannot do that because I went through Glo-cell. They have no office in Port Elizabeth and never return emails (customer service email does not exsist or call backs. Also the Samsung J1 that I was given as an "upgrade" is the worst phone EVA. I find it difficult to believe that I cannot get a new SIM with a Cell C number @ a Cell C store. I will be canceling my contract because of the atrocious service I have had to endure since Alcatech took over Cell C