Started FDO demo by bringing up individual service. However when i configure the owner service info package to access https, i get error on protocol 68

[snatar2]

Owner log snippet:
Example 1
22:23:10.975 [INFO ] HTTP(S) GET: https://www.google.com/search?q=ubuntu
22:23:11.345 [ERROR] failed to get http contentPKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
22:23:11.348 [INFO ] Type 255 [500, 68, "Unspecified error occurred.", 1738102991, 2936510917]

Example 2
21:49:25.186 [INFO ] HTTP(S) GET: https://raw.githubusercontent.com/snatar2/my_fdo/main/setup.sh
21:49:25.260 [ERROR] failed to get http contentPKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
21:49:25.262 [INFO ] Type 255 [500, 68, "Unspecified error occurred.", 1738100965, 165570108]

i couldn't resolve this issue while running the java version of FDO. However, i can access the website URL without any problem from Linux and Java. Any suggestions on how to resolve this?