Why are you installing a version which is going to be End-of-Life in October
this year?
Which operating system and version is it installed on? Centos7
How did you install it? I am installing Pjsip Package
Why? That is included in Asterisk 16 (and also Asterisk 18 and 20, which you
should be using instead for a new isntallation).
What documentation did you follow (provide URL) to do this? Asterisk 18
tls documentation
So, why aren’t you installing Asterisk 18? And, what’s the URL?
Please give far more detail about “how did you install it”? I’m talking
about the actual commands oyu used, so we can see whether they seem to be
correct, and could repeat them ourselves if needed.
Basically, the more information you give us to understand exactly what you
have done to get this error message, the more likely it is that someone can
help you to resolve the problem.