Elasticsearch multiple nested mapping error - elasticsearch

Question

I create an index for Elasticsearch and update mapping for that index, while doing this I use the same mapping as there is because I have reasons for it.
However, for the following situation, an error is returning that I don't understand, am I doing something wrong?
Thanks.
CREATE INDEX (Successful)
PUT /mytestindex
{
"mappings": {
"properties": {
"variable1": {
"type": "nested",
"include_in_parent": true,
"include_in_root": true,
"properties": {
"variable2": {
"type": "double"
},
"variable3": {
"type": "text",
"fields": {
"keyword": {
"type": "keyword"
}
}
},
"variable4": {
"type": "double"
},
"variable5": {
"type": "nested",
"include_in_parent": true,
"include_in_root": true,
"properties": {
"variable6": {
"type": "text",
"fields": {
"keyword": {
"type": "keyword"
}
}
}
}
}
}
}
}
}
}
UPDATE MAPPING AND RESPONSE
PUT /mytestindex/_mapping
{
"properties": {
"variable1": {
"type": "nested",
"include_in_parent": true,
"include_in_root": true,
"properties": {
"variable2": {
"type": "double"
},
"variable3": {
"type": "text",
"fields": {
"keyword": {
"type": "keyword"
}
}
},
"variable4": {
"type": "double"
},
"variable5": {
"type": "nested",
"include_in_parent": true,
"include_in_root": true,
"properties": {
"variable6": {
"type": "text",
"fields": {
"keyword": {
"type": "keyword"
}
}
}
}
}
}
}
}
}
{
"error" : {
"root_cause" : [
{
"type" : "mapper_exception",
"reason" : "the [include_in_root] parameter can't be updated on a nested object mapping"
}
],
"type" : "mapper_exception",
"reason" : "the [include_in_root] parameter can't be updated on a nested object mapping"
},
"status" : 500
}