Hi Richard - Welcome to the Atlassian Community!
You need to modify the Field Configuration used by that project.
Go to Settings > Issues > Field configurations
Search for the one used by the project and edit the configuration
Search for the field you want to be mandatory and click the Required option.
Hello @Richard John
Welcome to the community.
You cannot set a Locked field as Required through the field configuration.
You can set up a Validator in each Workflow Transition to validate that the field is not empty during status changes. That will require that the field be filled at least during status changes.
Which field are you trying to make required, and why?
For JSM June Challenge #2, share how your non-technical teams like HR, legal, marketing, finance, and beyond started using Jira Service Management! Tell us: Did they ask to start using it or...
Connect with like-minded Atlassian users at free events near you!Find an event
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no Community Events near you at the moment.Host an event
You're one step closer to meeting fellow Atlassian users at your local event. Learn more about Community Events