Error on reloading the res_pjsip.so

On the book:
The author says:

*CLI> pjsip show transports
Transport: <TransportId........> <Type> <cos> <tos> <BindAddress....................>
==========================================================================================
Transport: transport-tls tls 0 0 0.0.0.0:5061
Transport: transport-udp udp 0 0 0.0.0.0:5060

But in my system, I am not getting the transport-tls. I don’t know why it is missing:

Running as user 'asterisk'
Running under group 'asterisk'
Connected to Asterisk 16.14.0 currently running on localhost (pid = 1854)
localhost*CLI> pjsip show transports

Transport:  <TransportId........>  <Type>  <cos>  <tos>  <BindAddress....................>
==========================================================================================

Transport:  transport-udp             udp      0      0  0.0.0.0:5060

Objects found: 1

localhost*CLI> 

Please Help…

With Hope,
Prabhakaran