Bad management

I am battling to get hold of the manager at builders express. A member of the staff sold me a wrong product which damaged my basin. When I contacted the store, the manager offered a compensation and a refund. I sent someone in on my behalf. The manager gave the refund and R11 compensation. What a disgrace. My petrol got wasted. Now he does not return my calls. I would like to escalate this matter but the customer care line is also playing around