Gatling Report - Active users along the simulation

I have a simulation setup like this:

setUp(helloScenario.helloScn.inject(constantUsersPerSec(120) during(1800) randomized).protocols(httpProtocol))

when i see the generated report the active users are zero after the 17th min

any idea why?

gatling version - 2.2.4
scala version - 3.2.2

i attached the screen shot here.

![Auto Generated Inline Image 1.png|1152x966](upload://xrJ1ELOpljAEPySxJU3qVJW7gLl.png)!topic/gatling/im3quhfWr-E

Thank you Stéphane. i will update the version to 2.2.5