[Solved] License keys and Dev Environments

Hello, we recently upgraded from wpdiscuz version 5 to version 7.
we also upgraded wpDiscuz - Subscription Manager to version 7, and wpDiscuz - Comment Search to version 7.
We are doing this in a separate development environment, and doing test before upgrading live.
So far we are happy with the new features and changes in core wpdiscuz version 7.
The problem is we can not test Subscription Manager or Comment Search on DEV, because when we try to activate with the provided keys
it says "The number of activation exceeded limit. Please connect with support !".
The question is, do we need to purchase extra licences for our development environments? They all are subdomains of brainreference.com,
example: dev.brainreference.com, d02.brainreference.com, d03.brainreference.com
Is there a way to allow development subdomains to use the same keys, or do we need to purchase extra licences for our dev subdomains?

Thanks in advance.