DH has missed two appointments because letters took weeks to arrive.
I can do better than that.
Moved house 22 years ago. Around about the same time I had a referral to a local hospital from my GP. After a couple of months, I queried it. GP said the letter had been sent but I was a DNA. Re-referred me, Again heard nothing.
Then, just by luck, I popped past the old place and a neighbour had the letter for me (had forgotten to forward it). Sure enough it was the missing appointment.
Attended and told everyone to update my details.
Letters were still going to the old address.
This went on for over a year. Every time I complained, they checked my address was up to date (it was) and the mystery deepened.
Finally, about a year after then I had 2 separate tests and the consultant gave me my notes to take to the second appointment. Obviously I looked, and there, at the back was a sheet of pre printed labels with my old address. I threw them away and haven't had a problem since.
The worrying thing is I have escalated this through PALS and my MP, and every time the hospital has insisted they have never used labels. So it can't have happened. So I am a fantasist full of shit.
Also no one I have spoken to in any role at the hospital says they have ever used labels.