A phone number? What's that?

10 minutes into an already rather... Communicationally challenged phone-call, just when I had the problem solved:

"So I have another question. Can I ask you another question?"
"Of course ma'am"
"I couldn't log onto my desk-phone this morning. I tried and it didn't work."
"Alright... Let me see if there's a a problem with your log-in information." I had full control of her computer at this point and went to my company's telephone website. "Could you please enter your phone number here?"
"My phone number?"
"Yes, please enter your phone number where it says username."
"My phone number...?"
"Your phone number."
"My phone number?"
"Yes your phone number... Four digits that people dial when they call you on the phone."
"Oh my phone number! So I just write thisisanemailadress@stillanemail.com...?"
"Ma'am, a phone number usually consists of digits..."

In the end, it turns out that the phone number she had been trying to log on with was not, in fact, her phone number. As a matter of fact, the phone was logged on to her proper phone number all along.

(Note: In the company I work for, you only use the last four digits of a phone number when it's an internal call.)