Be aware - of telephone calls from 02064625449 telling you that they are calling from Microsoft or Windows Support, they are phishing attacks - do not carry on with the call
They will try and get you to go onto your computer, to give them access so that the can change some settings or install some software. Then they'll charge you to Fix your PC, which wasn't broken before they gained access.
Microsoft do NOT know if you have a PC, Nor will they call you.
If you have any issue with your PC go to a local PC repair place. DO NOT TRUST A RANDOM CALLER OFFERING TO FIX YOUR PC OR LAPTOP
Phishing is the attempt to acquire sensitive information such as usernames, passwords, and credit card details (and sometimes, indirectly, money), often for malicious reasons, by masquerading as a trustworthy entity in an electronic communication.