"The manner in which I was spoken to"

I phone to change an appointment as I only received it a few days before I was due to attend.

The way I was spoken to on the phone was nothing short of rude. 

I was told by the member of staff I spoke to that they can’t change it just now, they're too busy, the Clerkess will send a new one out and the phone was hung up very abruptly. 

I work for another NHS trust and find this behaviour unacceptable.  I am aware that the services are very busy and everyone is stretched but this is no excuse for the manner in which I was spoken to.