Cellphone lies

I had to recently replace my child's Cellphone. I apptoached the cellphone shop inside Checkers Hyper Vanderbijlpark who sold me a "very nice" Techno Pop phone for R700, 00. I was told therw was no comebacks but if my child was unhappy I could return the phone. When I tried to return the phone I was told I could not return the phone sorry they do not do returns.