[Local path chaining] SC Policy not able to copy headers of the request

Google Cloud Apigee
1

I have an API proxy A where I am using an SC policy (attached to target endpoint response flow) to call another API endpoint from another API proxy B using the local path-chaining method. I am copying some headers from A and use them in SC policy like this (tried to upload the image here but unable to do so, please fix):

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ServiceCallout async="false" continueOnError="false" enabled="true" name="SC-GetAllServices">
    <DisplayName>SC-GetAllServices</DisplayName>
    <FaultRules/>
    <Properties/>
    <Request clearPayload="true" variable="myRequest">
        <Copy source="request">
            <Headers>
                <Header name="tokenSource"/>
                <Header name="device"/>
            </Headers>
        </Copy>
        <IgnoreUnresolvedVariables>true</IgnoreUnresolvedVariables>
    </Request>
    <Response>getAllServicesResponse</Response>
    <LocalTargetConnection>
        <Path>/v1/services/mock/id</Path>
        <Properties/>
    </LocalTargetConnection>
</ServiceCallout>

One of the headers tokenSource is being passed to proxy B but another one header device is not.

I checked the trace but saw that from the specific point this header is not available in the trace in the request headers section. Please guide me here. @Dino-at-Google