As i mentioned you need to update through SSH, not the management console. Since you can see SP5 you are running the correct repository. Use the instructions for Debian in the following link to update your system. https://www.3cx.com/blog/news/pbx-upgrade-update-6/I tried to ugprade but it now shows me the option to upgrade to SP5. But I can't do that because it says license expired.... But my license is valid, but it can't get to SP6 to see it. What repository should I use. I used the upgrade repository you posted.
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