Please go through this list to establish the problem.

It is possible that your email client have send the confirmation email to your spam folder. Check folders like spam, junk E-mail etc on the date you have requested the fax number.

You may have entered a wrong email address. Resubmit your request it will tell you if the email is already registered or will send a new confirmation email you will have to choose a new fax number. You may also send a request here if you suspect you have entered the wrong email address and wish to keep the fax number you have requested.

Was the mail from an international source. If so Telkom have a restriction from international faxes please use your landline for International faxes.