Can you clarify what you mean by "the documentation speak to trigger the support" and where you are sending emails?
The Splunk Light documentation (http://docs.splunk.com/Documentation/SplunkLight/7.1.2/Installation/Aboutlicensing#Splunk_Light_license_types mentions that the free license is valid for one year. Is it possible that you need to request a renewal of your free license?
Any additional information you can provide about which version you were on before upgrading to 7.1.2, which operating system you are using, and how long you have been using the Splunk Light Free license might help the community to troubleshoot your situation.
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