Hello.
Looks like it is not new issue but thread in top as for License issue has a lot of unuseful info.
There is EP with in banded AppServer. It was upgraded from 7.2.1 to 7.2.3 and OD stopped to get valid license from SMGR.
URL is valid absolutely. Looks like something wrong with TLS handshake. Certificate from WebLM SMGR is loaded.
I remember I found once the solution and I couldn't find it again.
Clearing of trial timer is bad idea periodically.
Could you help me by good advice?
Rg, Dmitry

Take a look here, maybe it helps:

https://www.devconnectprogram.com/forums/posts/list/18454.page

Thank you massimo__croci but it is not solution. There are a lot of such messages like "please reset timer". It is not permanent solution.
Rg, Dmitry

The release note might help:

WebLM 8 client - The new WebLM client, which solves the https connection problem with
JBoss/Wildfly, requires a manual step to make it work. Particularly it requires the
trustedcert.properties file in a specific sub directory inside the app server deployment directory. The
directory is different for different app server type. For Tomcat, you have to copy the
trustedcert.properties from the lib directory into the webapps/WebLM/admin directory. Otherwise, you
would see an exception such as the following in the console log when configuring the https license url
in runtimeconfig or running the app for the first time. For other app server, take note of the similar
FileNotFoundException in the console log and move the trustedcert.properties to the sub directory
indicated in the exception.
java.io.FileNotFoundException: C:\OD723\deployment\apache-tomcat9.0.8\webapps\WebLM\admin\trustedcert.properties

Thank you for your answer. But WebLM is SMGR. It is not possible to copy certificates to it's folder.
Avaya doesn't give root password for SMGR for customers.
Rg, Dmitry

It doesn't matter what form the WebLM server is. The fact is OD has been using the weblm client library to retrieve the license. The weblm client in turn uses the certificate from the trusted_weblm_certs.jks truststore file which is located in the Tomcat/lib directory. So you have to make sure it has the right certificate from SMGR.

Yes. I am sure. I fetched it and and checked via SMGR. It is valid certificate. Looks like something wrong with TLS1.1/TLS1.2.

Finally I would like to put answer here for everyone.
The issue: After upgrade POM to 3.1.3 in banded AppServer lost license and couldn't get it from SMGR.
The solution is quite strange but it is working.
It's is here:
[root@pom lib]# pwd
/opt/AppServer/tomcat/lib
lrwxrwxrwx. 1 root root 60 Apr 18 23:03 trustedcert.properties -> /opt/Avaya/avpom/POManager/DDapps/lib/trustedcert.properties
[root@pom lib]# mkdir /opt/AppServer/tomcat/webapps/WebLM/
[root@pom lib]# mkdir /opt/AppServer/tomcat/webapps/WebLM/admin
[root@pom lib]# cp /opt/Avaya/avpom/POManager/DDapps/lib/trustedcert.properties /opt/AppServer/tomcat/webapps/WebLM/admin

After this action AppServer started to get license from SMGR. Restart of AppServer is not needed.
Rg, Dmitry