If they have JSD license, they will always have the option to add comments to the customers, and only training can help you with that, you can restrict that from Jira. There is the contributor role as well, that in that case comments are always internal but there are some other limitations as well, maybe that's what you are looking for. Take a look to this documentation to have all the differences between the different roles
We often have questions from folks using Jira Service Management about the benefits to using Premium. Check out this video to learn how you can unlock even more value in our Premium plan. &nb...
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