In JSD administration go to "Request security", and under "Manage who can raise requests through email and the customer portal", set it to "Only people on my customers list".
You then need to add the customer manually (or add the group they belong).
Some documentation links relevant to this:
Hey Community mates! Claire here from the Software Product Marketing team. We all know software development changes rapidly, and it's often tough to keep up. But from our research, we've found the h...
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