How to change the Jira Service Desk agents without changing the billing plan?

[Marella]

I'm very confused here! I choose he billing plan FREE (there are 3 Jira service desk agents). I deleted one agent and wanted to insert new one but I get the answer all the time that "You've reached the maximum, number of agents for Jira Service Desk on this plan. To add more agents, upgrade your plan." .
This is not normal. How to resolve this problem?

[Jack Brickey]

Unsure but consider that Admins count toward agents. You might reach out to Atlassian Support and use “billing question”. Even free plans get billing support. 

[Marella]

I got the solution already. Thank You!