Stop robocalls

Allegedly blocked by Microsoft Security. Unable to cancel screen. Flashing phone number 1800 024 406 claiming to be Microsoft Help. Long and detailed conversation then request to pay $199 to have my computer unlocked. Offered a follow-up number of 1800 921 675.

I believe this number is a scam number. A strange window popped up on my PC claiming my computer had been compromised and prompting me to call Microsoft Windows support on this number. I called, And went through a lengthy process in which the operator (XXXXX XXX) claimed that my computer had been used for, Among other things, Surfing child XXXXX sites, And that every other computer on my home network had also been compromised. Eventually he offered to sell me a system called Sonic Firewall whi