Magento 2 : Error does not have accessor method on vuestorefront

I’m trying to pass the custom option in vuestorefront api/cart/update call and trying to get it on sales_quote_product_add_after observer but I’m getting an error

[2021-08-17 13:54:40] main.CRITICAL: Report ID: webapi-611bbfa0d28e4; Message: Property “SingleSqmQty” does not have accessor method “getSingleSqmQty” in class “MagentoCatalogApiDataCustomOptionInterface”. {“exception”:”[object] (Exception(code: 0): Report ID: webapi-611bbfa0d28e4; Message: Property “SingleSqmQty” does not have accessor method “getSingleSqmQty” in class “MagentoCatalogApiDataCustomOptionInterface”. at /domains/qa.testing.co.uk/http/vendor/magento/framework/Webapi/ErrorProcessor.php:208, LogicException(code: 0): Property “SingleSqmQty” does not have accessor method “getSingleSqmQty” in class “MagentoCatalogApiDataCustomOptionInterface”. at /domains/qa.testing.co.uk/http/vendor/magento/framework/Reflection/NameFinder.php:103)”} []

the payload is like

  {"cartItem":
    {
    "sku":"440160",
    "qty":3,
    "product_option":{
      "extension_attributes":{
       "custom_options":[{"single_sqm_qty":true}],
       "configurable_item_options":[],
       "bundle_options":[]}},
    "sqm_qty":"single",
    "quoteId":"OAUYs3m2hw6zn9e8geqKYrjqnyA2bENH"}}

I’m trying to set single_sqm_qty named option in the custom option am I doing things wrong or what I have no idea about vuestorefront side