Pensioner done in by OK Furniture and Restonic

My mom bought 2 3/4 Restonic beds from OK furniture in Feb 2018, 9 month down the line the mattresses are falling apart, we went to the OK to report this as the beds are still under warranty and guarantee, to our surprise a representative of Restonic phone my mom and told her that the beds she bought was for kids only and not for adults. When we went to go and speak to the sales lady at the OK she did not no that the product was only for kids. My mom is a pensioner and are sitting with ad debt over 12 thousand rand that she must pay off for a product that is not up to standard. Restonic will replace the mattresses but with the same once my mom bought if my mom want an upgrade she must pay more. I believe if the sales people at OK had the knowledge of the product they are selling this would not have happen, I my mom muts not pay for the incompetence of the Staff at Restonic and OK Furniture