Trying to add a telephone number hyperlink like "tel:###" to an RTF template for BI email bursting

Summary:

I'm trying to add a clickable telephone number hyperlink like "tel:###" to an RTF template used for BI-Publisher email bursting.
According to this, it should be possible:
https://answers.microsoft.com/en-us/msoffice/forum/all/clickable-phone-numbers-in-word-documents/3ed057a0-789a-47c3-bdbc-f6592e848c4e
But when I try this, the link is mutes to:
\u01\APPLTOP\instance\domains\fa.oracleoutsourcing.com\FADomain\tel:####
instead.
The phone number in the email should become clickable, so the phone number is dialed when clicked.
How can I create a tel:### link in RTF where "###" is the phone number?

I tried entering "tel://########/" into the hyperlink