how to resolve clean the pop up error message: 268d3

When i open the safari i get the error message 268D3, it says the system will be locked out call the support emeadiately to resolve. The mac support number on the pop up shows up: 1888 501 1108. so then I called one person answers his name he said Mark Victor provided two phone numbers. he said 855 378 8884 X 1007. He asked me to type www.fastsupportl11@solutionfortech.com, and in the input field asked me to type: 668365774.

I listened to the guy but i did not go to the above site or entered the remote connection id it seems. I told him he is a scam. so now how to resolve this issue or clean up tool help.

Thanks,

Captainmetro54.