unable to send messages from hotmail. account

I have been unable to send messages from my hotmail account. It appears that I am getting all email. This problem has persisted for over a week. I called a number I found on the internet, however I am wondering if this was not a legitimate Helpdesk: 858-260-6355. They told me it was an issue with my IP address and they wanted to remote into my computer using a code. This did not seem helpful to me and I ended the call because I was worried it was a hacker. 

Any help would be appreciated!