Check and see that you are in the correct workpool.
There is a drop down to the right of the Designer Studio button. It will display the name of the Application you are in. Click on that and select Switch Work Pool to the workpool representing your application.
Typically this error occurs when you are trying to update casetypes related to rulesets which are locked and with no open ruleset versions.In your case you might be modifying some case type which belongs to PegaSample or some framework.