Defective Mattress Springs / sagging

Comfiflex Plush Mattress 183 E/L( King size. extra length). This was purchased from Ivor Garb, Durbanville 24/5/2008. The springs started to gouge the wooden base and eventually was \repaired"16/2/2012 under guarantee. Since 16/3/2015 I have been trying to get someone to examine the mattress as not only do springs continue to gouge the wooden base but pointed ends are protruding from the side walls (extremely dangerous!) and the bed sags as the springs appear to have also collapsed to the side. Since March I have been in touch with Tafelberg Furnishers and they have contacted Serta on my behalf but to no avail. The 15 year warranty covers loose"