Demystifying iControl REST Part 3 - How to pass query parameters and tmsh options

Running version 14.1.2.6, how can I filter on date? I have an ASM where I want to get all requests after a certain date

https://{{hostname}}/mgmt/tm/asm/events/requests?$filter=requestPolicy/createdDatetime+gt+'2020-07-28T00:00:00Z'&$select=requestPolicy/name,requestPolicy/createdDatetime,virtualServerName,serverIp,id,url,acceptStatus,responseContentType,violations/violationReference,enforcementMode,responseDatetime,clientIp,enforcementState/attackTypeReferences&$top=1

The response is

{
    "totalPages": 0,
    "pageIndex": 1,
    "selfLink": "https://localhost/mgmt/tm/asm/events/requests?$top=1&$select=requestPolicy%2Fname%2CrequestPolicy%2FcreatedDatetime%2CvirtualServerName%2CserverIp%2Cid%2Curl%2CacceptStatus%2CresponseContentType%2Cviolations%2FviolationReference%2CenforcementMode%2CresponseDatetime%2CclientIp%2CenforcementState%2FattackTypeReferences&ver=14.1.2&$filter=requestPolicy%2FcreatedDatetime%20gt%20%272020-07-28T00%3A00%3A00Z%27",
    "kind": "tm:asm:events:requests:requestcollectionstate",
    "startIndex": 1,
    "itemsPerPage": 1,
    "totalItems": 0,
    "items": []
}

When I run a query filtering on a specific ASM policy name I receive over 30.000+ items/requests

https://{{hostname}}/mgmt/tm/asm/events/requests?$filter=requestPolicy/name+eq+'{{asm-policy-name}}'&$select=requestPolicy/name,requestPolicy/createdDatetime,virtualServerName,serverIp,id,url,acceptStatus,responseContentType,violations/violationReference,enforcementMode,responseDatetime,clientIp,enforcementState/attackTypeReferences&$top=1

{
    "totalPages": 31980,
    "pageIndex": 1,
    "selfLink": "https://localhost/mgmt/tm/asm/events/requests?$top=1&$select=requestPolicy%2Fname%2CrequestPolicy%2FcreatedDatetime%2CvirtualServerName%2CserverIp%2Cid%2Curl%2CacceptStatus%2CresponseContentType%2Cviolations%2FviolationReference%2CenforcementMode%2CresponseDatetime%2CclientIp%2CenforcementState%2FattackTypeReferences&ver=14.1.2&$filter=requestPolicy%2Fname%20eq%20%27<asm-policy-name>%27",
    "kind": "tm:asm:events:requests:requestcollectionstate",
    "startIndex": 1,
    "itemsPerPage": 1,
    "totalItems": 31980,
    "nextLink": "https://localhost/mgmt/tm/asm/events/requests?$skip=1&$top=1&$select=requestPolicy%2Fname%2CrequestPolicy%2FcreatedDatetime%2CvirtualServerName%2CserverIp%2Cid%2Curl%2CacceptStatus%2CresponseContentType%2Cviolations%2FviolationReference%2CenforcementMode%2CresponseDatetime%2CclientIp%2CenforcementState%2FattackTypeReferences&ver=14.1.2&$filter=requestPolicy%2Fname%20eq%20%27<asm-policy-name>%27",
    "items": [
        {
            ...
            "responseDatetime": "2020-07-29T08:40:20Z",
            ...
        }
    ]
}

I've also tried to run the same query with 'requestDatetime' but still no items returned.