There is a new tech support scam making the rounds. Cyber criminals are calling you, claiming they are from Dell, and they even have the correct service tag of your Dell PC. Remember! Never give out personal information to someone who has contacted you randomly and tech support folks will NEVER ask for your password.
Here is the article from Knowbe4.com with more information: https://blog.knowbe4.com/scam-of-the-week-dell-tech-support-service-tag-hack.