Rak Ceramics India — cracks in wash basin

I have purchased five washbasins and five closets from rak brand. After six months from the purchase we found some cracks in all the washbasins. Now some are in a condition that at any moment it might break down. Items you supplied were defective. So kindly replace the defective items and find a clear solution to this problem. From a reputed company like rak we expect a prompt and immediate action in this matter