Safari on iOS will automatically recognize phone numbers and turn them into clickable links, even if the number added is plain text. In some instances, it could lead to the number not showing up for your mobile site.
You can add a format-detection meta tag, which stops numbers from being turned into links. You can add the following code to Avada > Options > Advanced > Code Fields > Space before :
Alternatively, you can add a href selector for styling using this CSS code snippet, which you can add to Avada > Options > Custom CSS:
a[href^=tel] {
color: inherit;
text-decoration: none;
}