Issue when updating triple with blank nodes using sqarql - sparql

Question

This is my query, this query works fine for nodes with no blank node
but the issue with arrives while updating with blank node
here those nodes get repeated 100 times after updating
DELETE {
it:4D9AT21jAasfL9ah schema:description ?o_0 .
it:4D9AT21jAasfL9ah it:hasArea ?o_1 .
?o_1 rdf:type ?o_1_0 . ?o_1 schema:unitCode ?o_1_1 .
?o_1 schema:value ?o_1_2 . ?o_1 schema:unitText ?o_1_3 .
it:4D9AT21jAasfL9ah it:unresolvedWikidataType ?o_2 .
it:4D9AT21jAasfL9ah schema:longitude ?o_3 .
it:4D9AT21jAasfL9ah schema:addressCountry ?o_4 .
it:4D9AT21jAasfL9ah rdfs:label ?o_5 .
it:4D9AT21jAasfL9ah rdf:type ?o_6 .
it:4D9AT21jAasfL9ah schema:url ?o_7 .
it:4D9AT21jAasfL9ah it:wikiLink ?o_8 .
}
INSERT {
it:4D9AT21jAasfL9ah schema:description 'city and capital of Bali, Indonesia' .
it:4D9AT21jAasfL9ah it:hasArea _:bQRrRFzX1zv9qUGWy .
_:bQRrRFzX1zv9qUGWy rdf:type schema:QuantitativeValue;
schema:unitCode 'KMK';
schema:value '123.98';
schema:unitText 'km²' .
it:4D9AT21jAasfL9ah it:unresolvedWikidataType 'Q3199141', 'Q13220204' .
it:4D9AT21jAasfL9ah schema:longitude '115.21666666667' .
it:4D9AT21jAasfL9ah schema:addressCountry it:WtC49aYLe8s0lsFC .
it:4D9AT21jAasfL9ah rdfs:label 'Denpasar' .
it:4D9AT21jAasfL9ah rdf:type schema:City .
it:4D9AT21jAasfL9ah schema:url <http://www.denpasarkota.go.id/> .
it:4D9AT21jAasfL9ah it:wikiLink <https://en.wikipedia.org/wiki/Denpasar> .
}
WHERE {
it:4D9AT21jAasfL9ah ?p ?o .
OPTIONAL { it:4D9AT21jAasfL9ah schema:description ?o_0 }
OPTIONAL { it:4D9AT21jAasfL9ah it:hasArea ?o_1 }
OPTIONAL { ?o_1 rdf:type ?o_1_0 }
OPTIONAL { ?o_1 schema:unitCode ?o_1_1 }
OPTIONAL { ?o_1 schema:value ?o_1_2 }
OPTIONAL { ?o_1 schema:unitText ?o_1_3 }
OPTIONAL { it:4D9AT21jAasfL9ah it:unresolvedWikidataType ?o_2 }
OPTIONAL { it:4D9AT21jAasfL9ah schema:longitude ?o_3 }
OPTIONAL { it:4D9AT21jAasfL9ah schema:addressCountry ?o_4 }
OPTIONAL { it:4D9AT21jAasfL9ah rdfs:label ?o_5 }
OPTIONAL { it:4D9AT21jAasfL9ah rdf:type ?o_6 }
OPTIONAL { it:4D9AT21jAasfL9ah schema:url ?o_7 }
OPTIONAL { it:4D9AT21jAasfL9ah it:wikiLink ?o_8 }
}
This is the output in json format,
and only hasArea which has blank node values is being repeated many times
"schema:latitude": [
"-7.164444444444444"
],
"it:hasArea": [
{
"rdf:type": [
"schema:QuantitativeValue"
],
"schema:unitCode": [
"KMK"
],
"schema:value": [
"392.47"
],
"schema:unitText": [
"km²"
]
},
{
"rdf:type": [
"schema:QuantitativeValue"
],
"schema:unitCode": [
"KMK"
],
"schema:value": [
"392.47"
],
"schema:unitText": [
"km²"
]
},
{
"rdf:type": [
"schema:QuantitativeValue"
],
"schema:unitCode": [
"KMK"
],
"schema:value": [
"392.47"
],
"schema:unitText": [
"km²"
]
},...
],
"rdfs:label": [
"Denpasar"
],
...
Thanks in advance