BulwarkLabs.com are among the call centres who have calls diverted from this number: +1 844 692 6305.
The number appears in a popup: adsee.in/mozilla/us (replace us with gb for a UK number 0800 046 5731 number). Their fake popup describes the problem as a "Malicious Pornographic Spyware".
BulwarkLabs attempt to sell you their "Bulwark Privacy Wall" software. No doubt it's as fake as their support.
Use this URL if you want to examine their payment gateway in more detail: