Hi @netology,
Wordfence is an endpoint firewall designed to mainly check for malicious files on your site, limit brute force attempts to log in, rate limit high-volume or malicious access. Whilst we do have other useful features for protecting WordPress sites and their files, a telephone number such as <a href="tel:00000000000">...
is plainly clickable on your site but doesn’t behave like a form submission that could be blocked or have reCAPTCHA put in front of it with Wordfence.
If you’re using a plugin to generate the links, or the calls are from a live-chat style popup on your site, you may need to ask if they have features to filter out bots from trying to click.
Thanks,
Peter.