Getting "Unexpected character encountered" ERROR when generating for Sisense

[CicheR]

Command used: autorest --input-file=v1.json --csharp --output-folder=Hub.Sisense.Client --namespace=Hub.Sisense.Client

ERROR obtained: https://drive.google.com/file/d/1LeZLZyOCtAviyHj4tUd7oL0IoNRJTaKp/view?usp=sharing

JSON file: https://drive.google.com/file/d/1fa8dhIHschiV70UAiID4aK-HxfpE4pE0/view?usp=sharing

[CicheR]

JSON file was validated using: http://online.swagger.io/validator/debug

Result:

{
    "messages": [
        "attribute paths.'/elasticubes/getElasticubes'(post).operationId is repeated",
        "attribute paths.'/dashboards/{id}/change_owner'(post).operationId is repeated",
        "attribute paths.'/connection/{id}/table_schema_details'(post).operationId is repeated",
        "attribute paths.'/connection/{id}/table_preview'(post).operationId is repeated"
    ],
    "schemaValidationMessages": [
        {
            "level": "error",
            "domain": "validation",
            "keyword": "format",
            "message": "string \"^\\s*(?:\\(\\s*((?:[a-zA-Z0-9.!#$%&'*+/=?^_`{|}~-\\s]*)[a-zA-Z0-9.!#$%&'*+/=?^_`{|}~-]+)\\s*\\))?\\s*([a-zA-Z0-9.!#$%&'*+/=?^_`{|}~-]+@[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?(?:\\.[a-zA-Z0-9](?:[a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?)*)\\s*$\" is not a valid ECMA 262 regular expression",
            "schema": {
                "loadingURI": "http://json-schema.org/draft-04/schema#",
                "pointer": "/properties/pattern"
            },
            "instance": {
                "pointer": "/definitions/beginActivate/properties/email/pattern"
            }
        }
    ]
}