Getting error while trying to validate the header against oas policy

[Teja]

When I'm trying to validate the request content against the oas policy by passing the required header named X-My-Header which is an type of array, there were no errors when I sent one value in that header but whenever I'm trying to send multiple values in it
Getting error like this:

"OASValidation OpenAPI-Spec-Validation-1 with resource \"oas://OpenAPI-Spec-Validation-1.yaml\": failed with reason: \"[ERROR - Parameter 'X-My-Header' expected an array style of 'simple' [explode=false].: []]\""

I got to know that for headers default serialization method is simple style with 

explode=false which means comma-separated values But even when Im sending in that way also getting error

Here is the spec parameter part: (using spec version 3.0.1)

X-My-Header:
      name: X-My-Header
      in: header
      description: test
      required: true
      schema:
        type: array
        items:
          type: number
          enum: 
            - 1
            - 2

 Please help me here. Thanks in advance