The sell items they don’t have on stock and don’t refund you in time when you want refund

I called them and made quotations of 5 pallets of Maxi Bricks and eventually bought from them, i was not told they are out of stock and when i sent a truck for collection they returned and said the shop is out of stock, i asked for refund and at this moment its been 2 weeks without being refunded. Whenever i call them they give me lame excuses.