This is a scam. Please don’t call the number.
1. Force Quit .
Press command + option + esc keys together at the same time. Wait.
When Force Quit window appears, select Safari if not already.
Press Force Quit button at the bottom of the window. Wait.
Safari will quit.
2. Relaunch Safari holding the shift key down.
3. Turn off wifi and turn it back on.
Turn off Wifi. Click Wifi icon in the menu bar and select “Turn Wifi off”.
Visit another website.
You won’t have internet connection.
Turn on Wifi. Click Wifi icon in the menu bar and select “Turn Wifi on”.
Select your Network.
4. Safari > Preferences > Privacy
Cookies and website data:
Click “Details” button.
Remove the cookie related to this, if there is one.