F5OS download backup via API

Hi there,

I need to create and download F5OS backup via API.

I checked the documentation  I could find, but even I use content-type header as described (first time I see 2 Content-type headers at the HTTP header, but OK) but I keep getting this:

415 (Unsupported media type)


<errors xmlns="urn:ietf:params:xml:ns:yang:ietf-restconf">
    <error>
        <error-type>application</error-type>
        <error-tag>malformed-message</error-tag>
        <error-message>Unsupported media type: multipart/form-data; boundary=--------------------------821439130941430490548847 ; Should be one of: application/yang-data+json, application/yang-data+xml.</error-message>
    </error>
</errors>

Looke like Content-type: multipart/form-data is not supported even though the documentation guides me to use it. Anyone knows what to do with this?

Thanks