Hello guys,
I need your help to create a validation rule I've tried everything and I can't, the rule is as follows:

Create a validation rule on the Price Request object that does not allow you to change the Price Request status from "Unsolicited" to "Requested" in the "Order attached?" left equal to False. Rule logic:
"Status" field has been changed;
Field “Status” equal to “Requested”;
Field "Request attached?" equals False;
Error Message: The MS Excel Request File Was Not Attached.

When I tried to do it, I also got an error:
Error: State_CHI__c field is a picklist field. Picklist fields are only supported in certain roles

Can you help me? Thanks!