The problem is solved; The root certificate I had was not the right one. It was an intermediate certificate that did not refer our server. There was another certificate lower level than the one I was using which was not available on the Amazon site. I retrieved this one and now I can communicate with the server. Thank you for your help.
have you tried to make some tests with another device, for example a PC with OpenSSL, in order to check if the issue is related to a bad configuration or a wrong certificate?
If you can post the output of the following command:
The problem is solved; The root certificate I had was not the right one. It was an intermediate certificate that did not refer our server. There was another certificate lower level than the one I was using which was not available on the Amazon site. I retrieved this one and now I can communicate with the server. Thank you for your help.