I didn't find approval process in the free version. Is there any way to enable the feature, I want to do a test on the feature to see if it could fulfill our request.
The 14 day trial of the full version has the approval process for testing. It includes all of the features. Approval process would be under Setup->Processes->Approval Processes as well as have the sections for the approver setup as well.
There is a link on this page along with the comparison between the free and full versions.
https://www.solarwinds.com/free-tools/free-help-desk-software
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