Defy poor quality and service

I recently purchased a Defy gas 5 burner on glass hob. After 6 months it has cracked. The supplier was prepared to replace it as Defy had not made any contact after 7 weeks after lodging a complaint with them and the crack having been acknowledged by a Defy service man. A new hob was then brought to my home only to find that it too had a crack in it. We then returned it to the supplier who opened a 3rd hob, brand new out of the box. It too was cracked. I then went to a different service provider and tested a glass hob that was on the show ground floor. It was also cracked. And so after 38 years of having 5 glass top hobs, I sadly have realized that Defy glass hobs are no longer a viable proposition. I query whether their glass is an inferior quality????? How is it that 5 brand new appliances all have cracks in them. More than that the service from Defy is very very poor. Covoid used as an excuse. There is no excuse for poor service. I am an extremely disappointed Defy customer.