Very bad service 😒

I went to buy trusses at Chamberlain centurion and I was assisted by Andre.i was buying roofing material. I insisted on buying material that is available at the store as I didn't want to pay double delivery and felt like the supplier delivery was very pricy.he said if he takes stock from the shop it will be pricy is better if he orders for me because it only takes two days for their supplier to deliver material.the delivery date has passed and when I call him to find out what's happening he says the next day.its been the next day for past two days now.i then decided to call the manager werner to assist but he always promises to call but never calls back .when I keep on insisting on calling he transfers me to a guy called Shaun to Assist who also promised to callback but he never did. I m just frustrated because I wouldn't have hang my trusses if I new that the won't be tiles coming as they are going to be damaged by the rain . have been paying guys on site for nothing as they where waiting for tiles and no one returns your calls as promised.

So now what's going to happen to the trusses if they get damaged by water?