Data Load error from API

Hi,BI11 .Thank you for your reply.
In fact I followed up by creating a test case to completely simulate the problem you are experiencing.

Forgive me for not being very good at power query, but I made this simple example by searching the web and following the tutorials, according to the screenshot you can see that my result here corresponds to yours
This is my test code: (complete and correct M code)

let
    // API base URL
    baseUrl = "https://data.gov.uk/api",
// POST request data, including query parameters
    postData = Json.FromValue([
        x = 235.7,
        y = 41.53,
        q = "cows",
        rows = "20"
    ]),
// Request headers
    headers = [#"Content-Type" = "application/json"],
// Send POST request
    response = Web.Contents(
        baseUrl,
        [
            RelativePath = "3/action/package_search",
            Headers = headers,
            Content = postData
        ]
    ),
// Parse JSON response
    jsonResponse = Json.Document(response),
// Extract data from the results list
    resultData = jsonResponse[result],
    resultsList = resultData[results],
// Get all field names from the records
    allFieldNames = List.Distinct(List.Combine(List.Transform(resultsList, each Record.FieldNames(_)))),
// Convert results list to table
    resultsTable = Table.FromList(resultsList, Splitter.SplitByNothing(), null, null, ExtraValues.Error),
// Expand all fields in the records
    expandedTable = Table.ExpandRecordColumn(resultsTable, "Column1", allFieldNames)
in
    expandedTable

Here is the M code that I reproduced your question.
error M code

// Parse JSON response
    jsonResponse = Json.Document(response),
// Extract items list from the result record
    resultData = jsonResponse[result],
    itemsList = resultData[items]       //Here's the issue.
in
    itemsList

I've also uploaded the pbix I used for testing, and links to articles that were helpful to me, so I hope that helps.

URL:
Web.Contents - PowerQuery M | Microsoft Learn

Chris Webb's BI Blog: Using The RelativePath And Query Options With Web.Contents() In Power Query And Power BI M Code

The site can be accessed directly

The final result:(Data from the web)

I hope my suggestions give you good ideas, if you have any more questions, please clarify in a follow-up reply.
Best Regards,
Carson Jian,
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