We updated our "First Source" global picklist and our "Lead Source" value to include 'Salesforce'. We do not have record types on leads, contacts, or accounts (opportunity record types were updated to include the new values). I updated process builder to set the first source and lead source to the 'Salesforce' value for the fields when they are NULL but I get the error below.
Error element myRule_5_A1 (FlowRecordUpdate). The flow tried to update these records: 00Q1U00000WQKjxUAH. This error occurred: INVALID_OR_NULL_FOR_RESTRICTED_PICKLIST: First Source: bad value for restricted picklist field: Lead Source.
Our lead source field and first source field mirror each other except for the fact that first source is a global picklist which I recently added the new value.