I'm trying to build a script that I can use in some automation processes and I need to pull requester and technicians details and I've tried building something with the API documentation but I'm currently getting a 3001 - Unknown error statuscode.

My Current Code:

$ciname = "Test Tech"

[xml]$input_xml = @"

<?xml version='1.0' encoding='UTF-8'?>

<API version='1.0'>

    <citype>

        <name>Technician</name>

        <criterias>

            <criteria>

                <parameter>

                    <name compOperator='CONTAINS'>CI Name</name>

                    <value>$ciname</value>

                </parameter>

            </criteria>

        </criterias>

        <returnFields>

            <name>CI Name</name>

        </returnFields>

    </citype>

</API>

"@

$techkey = "TECH___KEY___"

$ReadTechURL = "https://domain.com/api/cmdb/ci/"

$ReadTechHeader = @{TECHNICIAN_KEY=$($techkey);OPERATION_NAME="read"}

$res = Invoke-RestMethod -URI $ReadTechURL -Method POST -Headers $ReadTechHeader -Body $input_xml -ContentType "application/xml"

$res.API.response.operation.result

I'll take any and all tips or suggestions here cause I'm stumped.