Online order not delivered

I purchased a gas cylinder with delivery through the Builders Warehouse website on the 14th July 2020. To date I still have not received my order. I have spoken to your online chat team numerous occasions and nobody can provide me with any update as to why my order hasn't been delivered. I also logged a call on the Builders Warehouse website on the 28th July 2020 and received an email response stating that somebody would be in touch with me within 48 hours. This still hasn't happened and still waiting for my order to be delivered.