Potential causes include:

1. You are not the owner of the change request.
2. The change request is not in progress.
3. The rule instance that you want to edit is checked out by another operator in Dev Studio.

1. In the Customer Decision Hub portal dashboard, check whether the change request is in progress and assigned to the correct operator.
2. Ask a system architect to take the following actions in Dev Studio:
   1. Check whether the rule instance is checked out by another operator.
      For more information, see Checking out a rule.
   2. Check the rule instance for compilation errors and fix any errors that you find.
   3. On the Security tab of the Operator ID, select Allow rule check out.
   4. Check whether the branch ruleset for the application overlay is present.