[Python] xmlsec reference with URI

I'm using the XMLSec library to sign a file. I need to use the specific algorithms listed below and include the invoice identification number in the reference URI. However, when the URI parameter is filled, the document is not signed, but if I leave it empty, the signature is generated successfully. I've already checked the ID, and everything seems correct.

Example ID: #NFCom43253123827184000163620017659731731076965182

Problem?

ref = xmlsec.template.add_reference(
signature, xmlsec.constants.TransformSha1, uri=f"#{id_nfcom}"
)

def assinar_xml(xml_tree, certificado_pem):
root = xml_tree.getroot()

inf_nfcom = root.find(".//{http://www.portalfiscal.inf.br/NFCom}infNFCom")
if inf_nfcom is None:
raise ValueError("Elemento <infNFCom> não encontrado no XML.")

id_nfcom = inf_nfcom.get("Id")
if not id_nfcom:
raise ValueError("Atributo 'Id' não encontrado no elemento <infNFCom>.")

signature = xmlsec.template.create(
root, xmlsec.Transform.C14N, xmlsec.Transform.RSA_SHA1
)

**ref = xmlsec.template.add_reference(
signature, xmlsec.constants.TransformSha1, uri=f"#{id_nfcom}"
)**

xmlsec.template.add_transform(ref, xmlsec.Transform.ENVELOPED)
xmlsec.template.add_transform(ref, xmlsec.Transform.C14N)

key_info = xmlsec.template.ensure_key_info(signature)
x509_data = xmlsec.template.add_x509_data(key_info)
xmlsec.template.x509_data_add_certificate(x509_data)

root.append(signature)

ctx = xmlsec.SignatureContext()

key = None
try:
key = xmlsec.Key.from_file(certificado_pem, xmlsec.constants.KeyDataFormatPem)
print("Chave carregada com sucesso!")
except Exception as e:
print(f"Erro ao carregar a chave: {e}")

if key is None:
raise ValueError("A chave não foi carregada corretamente.")

ctx.key = key

ctx.sign(signature)

return xml_tree

# xml BEFORE SIGNATURE #

<NFCom xmlns="http://www.portalfiscal.inf.br/NFCom">
<infNFCom Id="NFCom43253123827184000163620017659731731076965182" versao="1.00">
<ide>
<cUF>43</cUF>
<tpAmb>2</tpAmb>
<mod>62</mod>
<serie>1</serie>
<nNF>765973173</nNF>
<cNF>7696518</cNF>
<cDV>2</cDV>
<dhEmi>2025-01-31T11:56:18-03:00</dhEmi>
<tpEmis>1</tpEmis>
<nSiteAutoriz>0</nSiteAutoriz>
<cMunFG>3205309</cMunFG>
<finNFCom>0</finNFCom>
<tpFat>0</tpFat>
<verProc>1.00</verProc>
</ide>
<emit>
<CNPJ>23827184005463</CNPJ>
<IE>9071339235</IE>
<IEUFDest>321</IEUFDest>
<CRT>1</CRT>
<xNome>TELECOM LTDA ME</xNome>
<xFant>Telecom</xFant>
<enderEmit>
<xLgr>AV. PRESIDENTE KENNEDY</xLgr>
<nro>845</nro>
<xBairro>Centro</xBairro>
<cMun>4117909</cMun>
<xMun>Palotina</xMun>
<CEP>85950000</CEP>
<UF>PR</UF>
</enderEmit>
</emit>
<dest>
<xNome>Cliente de Telecomunicações Ltda</xNome>
<CNPJ>98765432000187</CNPJ>
<indIEDest>1</indIEDest>
<IE></IE>
<IM>1</IM>
<enderDest>
<xLgr>Rua das Comunicações</xLgr>
<nro>123</nro>
<xBairro>Centro</xBairro>
<cMun>3205309</cMun>
<xMun>Vitória</xMun>
<CEP>85950000</CEP>
<UF>ES</UF>
</enderDest>
</dest>
<assinante>
<iCodAssinante>01</iCodAssinante>
<tpAssinante>1</tpAssinante>
<tpServUtil>4</tpServUtil>
</assinante>
<det nItem="1">
<prod>
<cProd>001</cProd>
<xProd>Serviço de Internet Banda Larga</xProd>
<cClass>0400401</cClass>
<CFOP>5303</CFOP>
<uMed>2</uMed>
<qFaturada>100.00</qFaturada>
<vItem>100.00</vItem>
<vProd>100.00</vProd>
</prod>
<imposto>
<ICMS00>
<CST>00</CST>
<vBC>10.00</vBC>
<pICMS>18.00</pICMS>
<vICMS>1.80</vICMS>
</ICMS00>
</imposto>
</det>
<total>
<vProd>100.00</vProd>
<ICMSTot>
<vBC>10.00</vBC>
<vICMS>1.80</vICMS>
<vICMSDeson>1.00</vICMSDeson>
<vFCP>1.00</vFCP>
</ICMSTot>
<vCOFINS>1.00</vCOFINS>
<vPIS>1.00</vPIS>
<vFUNTTEL>1.00</vFUNTTEL>
<vFUST>1.00</vFUST>
<vRetTribTot>
<vRetPIS>1.00</vRetPIS>
<vRetCofins>1.00</vRetCofins>
<vRetCSLL>1.00</vRetCSLL>
<vIRRF>1.00</vIRRF>
</vRetTribTot>
<vDesc>0.00</vDesc>
<vOutro>1.00</vOutro>
<vNF>100.00</vNF>
</total>
</infNFCom>
<infNFComSupl>
<qrCodNFCom>http://dfe-portal.svrs.rs.gov.br/NFCom/QRCode?chNFCom=43120201234567890123456789012345678901234567&amp;tpAmb=2</qrCodNFCom>
</infNFComSupl>
</NFCom>

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