The problem is that the schema you're using has the elementFormDefault option set to "qualified", which means child elements must also be inside the target namespace of the schema. The instances you're using don't conform to this. For example, you have this:
<ns0:ResponseEmpresa xmlns:ns0="SIARP:Empresa">
<GRAL_MA_EMPRESA>
<ID_TIPO_DOC />
<ID_EMPRESA />
…
When you should have this:
<ns0:ResponseEmpresa xmlns:ns0="SIARP:Empresa">
<ns0:GRAL_MA_EMPRESA>
<ns0:ID_TIPO_DOC />
<ns0:ID_EMPRESA />
…
Or this (which is equivalent)
<ResponseEmpresa xmlns="SIARP:Empresa">
<GRAL_MA_EMPRESA>
<ID_TIPO_DOC />
<ID_EMPRESA />
…
Either fix your messages, or fix your schema.