Welcome to the community forum. I am sorry to hear your engineers appointment was missed. I can take a look at your order, to see what is going on. Please send me in your details using the "Contact The Mods" link found in my profile.
It's shocking isn't it. I've posted my tale of woe on here. BT seems to employ loads of people to say sorry, and send you a link to post your concern into the abyss. Cancelling is probably the only logical thing to do.