Indicator set to block, but I'm still prompted for approval

Yesterday I added a malicious file indicator and set it to Alert and Block (side note: Block only would be great to have).  This morning another user in my environment came across the file, but it did NOT quarantine the file-- I had to approve it.  How can I have an indicator automatically quarantined?  I created the indicator because I know it's evil. 

I'm thinking/hoping that this isn't related to the remediation level setting - because the choices there are more broad and don't speak to indicators.

Thank you so much for help in advance!