When submitting a test or multi test, following error may show up:
Blazemeter SaaS
Your test is configured to use more engines than your billing plan allows. To check your billing plan, go to Settings > Account > Billing (only owners and admins are able to check this).
You need to decrease the number of engines that your test uses, see the Engine Count section in this article on how to do that.
For multi tests the engine count is determined by adding up the engines used by each scenario. You will need to decrease the number of engines of one or more scenario until the total no longer exceeds your plan's limit.