HR Help Desk - make Category mandatory

Summary:

An employee/agent can create a service request by only providing the Title. However, fields like Category, Primary Contact and Problem description are also important, and need to be made mandatory. Any idea how can we achieve this?

I tried to modify the fields using Application Composer, but the fields are disabled for any modifications. Primary Contact Required property is selected as Yes, but still it is not mandatory.

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21D

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