I am using AWS generated SDK for JavaScript to API Gateway post method and following is API gateway information.

<script type="text/javascript"src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
<script type="text/javascript" src="lib/axios/dist/axios.standalone.js"></script>
<script type="text/javascript" src="lib/CryptoJS/rollups/hmac-sha256.js"></script>
<script type="text/javascript" src="lib/CryptoJS/rollups/sha256.js"></script>
<script type="text/javascript" src="lib/CryptoJS/components/hmac.js"></script>
<script type="text/javascript" src="lib/CryptoJS/components/enc-base64.js"></script>
<script type="text/javascript" src="lib/url-template/url-template.js"></script>
<script type="text/javascript" src="lib/apiGatewayCore/sigV4Client.js"></script>
<script type="text/javascript" src="lib/apiGatewayCore/apiGatewayClient.js"></script>
<script type="text/javascript" src="lib/apiGatewayCore/simpleHttpClient.js"></script>
<script type="text/javascript" src="lib/apiGatewayCore/utils.js"></script>
<script type="text/javascript" src="apigClient.js"></script>

var apigClient = apigClientFactory.newClient({apiKey: 'GF58475hjghg8ererb45hgfsdf', region: 'ap-south-1'});
var body = {"key1": "My Value"};
apigClient.testMyApiPost(null, body)
  .then(function(result){
    console.log("success : "+result)
}).catch( function(result){
    console.log("error : "+result)
});

but i am getting error apigClient.testMyApiPost is not a function even I have tried many combinations as method name, still same issue.

Please help, Thanks :)