Serverless alb event does not list of query params

So i have a serverless app where i am sending the request to an alb which gets redirected to a lambda function. My request is /?filePath=a&filePath=b&filePath=c&filePath=d&pageSize=2 but in the event being passed to the lambda its shown as below:-

   "requestContext": {
    "elb": {
        "targetGroupArn": "xyz"
 "httpMethod": "GET",
 "path": "/xyz",
 "queryStringParameters": {
     "filePath": "d",
     "page": "1",

I have verified that multiValueQueryStringParameters is set to true in events
- alb:
listenerArn: XXX
priority: 2
multiValueQueryStringParameters: true
path: XXX
method: GET
- http:
path: XXX
method: GET