I'm dealing with a company at the moment where the interaction tends to go like this:

1. They call my mobile number, but I am not available.

2. They email me to say that they can't get hold of me and ask me to phone them.

3. I contact their customer support on Twitter who tell me what the original message was.

Simply sending me the message by email in the first place would save some time. I'd also then have a log of any discussion, which I don't get on the telephone (but they record conversations).