Phone network locked after ensuring me it isn't

<p>Yesterday I went into Game store to purchase the Vodafone Kicka 2 for cash. When querying about using my cell c sim in the phone I was advised that they had some clients returning saying the phone had locked after about a week of using another network sim. I was directed to The Vodacom store. The gentleman (Yusuf) and lady that assisted me that their handsets were not network locked and they also confirmed with their manager at the back. Not even 24 hours later and the phone has been locked for hours because I am using my Cell C sim. This phone was not advertised as being network locked and I ensured it wasn't before purchasing it. I do not wish to do a sim swop as I only use WhatsApp on the phone and Vodacom is much more expensive. Please provide me with a speedy resolution to this issue. This is unnecessary and unacceptable problem. </p>