Where to download incremental patch?

Hi,

I am on 15.0.3 (build 143.1821) and I want to update to 15.0.5 (build 143.2332). I do not get the "Update and restart" button when checking for updates. I only have the option to click "Download" which brings me to the page to download version 2016 but my organization does not have a license for that. How can I get the patch or the full installer for 15.0.5?

Thank you.