No sim swop

I tried to do a sim swop as my cell phone was ******, the stores had no sims in stock. When I asked if they could call another store to find one which had and they said I must call. I called the call centre as everytime I try to call a store the call is cut, they informed me that they cannot assist, the people at the store are lying as they must find out from other stores and inform me where to go.