Xml - Cannot Find The Declaration Of Element 'Document'., Line '1', Column '11'?

currently I am trying to validate my XML against my XSD, however, I am getting always this error message:

Cannot Find The Declaration Of Element 'Document'., Line '1', Column '11'.

and I do not know/understand how to fix it?

Here is my XSD:

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns="rn:iso:std:iso:20022:tech:xsd:uth.30.01.3" xmlns:xs="http://www.w3.org/2001/XMLSchema" elementFormDefault="qualified" targetNamespace="rn:iso:std:iso:20022:tech:xsd:uth.30.01.3">
    <xs:element name="Document" type="Document"/>
    <xs:simpleType name="ActiveCurrencyCode">
        <xs:annotation>
            <xs:documentation source="Name" xml:lang="EN">ActiveCurrencyCode</xs:documentation>
            <xs:documentation source="Definition" xml:lang="EN">A code allocated to a currency by a Maintenance Agency under an international identification scheme as described in the latest edition of the international standard ISO 4217 "Codes for the representation of currencies and funds".</xs:documentation>
        </xs:annotation>
        <xs:restriction base="xs:string">
            <xs:pattern value="[A-Z]{3,3}"/>
        </xs:restriction>
    </xs:simpleType>

and here goes the XML

<?xml version='1.0' encoding='utf-8'?>
<Document>
    <DerivsTradRpt>
        <RptgTmStmp>2024-03-13T13:24:23Z</RptgTmStmp>
        <TradData>
            <Rpt>
...
        </TradData>
    </DerivsTradRpt>
</Document>

Maybe, someone can help me, please!

Thank you very much in advance.