Release Indicator error in the Log

Hi,

I'm in Workflow, while building the purchase req release workflow, the Released event is not triggered. I went into the SPRO and checked the release strategy, and read the following error msg in the log,

Define a release indicator for the status "released"

But under 'Setup procedure with classification', in Release Indicator, we've already assigned '2' to status 'PR Released', and in Release strategy, assigned the release status to all strategies in use.

Any ideas why the error msg is still there?

Many thanks,

Kathryn