Request token retrieval failed:

RESPONSE:

Array
(
    [linkedin] => Array
        (
        )

    [info] => Array
        (
            [url] => https://api.linkedin.com/uas/oauth/requestToken
            [content_type] => 
            [http_code] => 410
            [header_size] => 548
            [request_size] => 516
            [filetime] => -1
            [ssl_verify_result] => 0
            [redirect_count] => 0
            [total_time] => 5.628467
            [namelookup_time] => 5.514077
            [connect_time] => 5.51516
            [pretransfer_time] => 5.525135
            [size_upload] => 0
            [size_download] => 0
            [speed_download] => 0
            [speed_upload] => 0
            [download_content_length] => 0
            [upload_content_length] => -1
            [starttransfer_time] => 5.628453
            [redirect_time] => 0
            [redirect_url] => 
            [primary_ip] => 185.63.145.4
            [certinfo] => Array
                (
                )

            [primary_port] => 443
            [local_ip] => 172.16.36.12
            [local_port] => 35410
            [http_version] => 2
            [protocol] => 2
            [ssl_verifyresult] => 0
            [scheme] => HTTPS
        )

    [oauth] => Array
        (
            [header] => Authorization: OAuth realm="http%3A%2F%2Fapi.linkedin.com",oauth_version="1.0",oauth_nonce="c817ff5679255fa456f09926883ca391",oauth_timestamp="1600935936",oauth_consumer_key="77en7xz71dzcr5",oauth_callback="https%3A%2F%2Fkarriere.findingheads.de%3A443%2Fxing%2Flinkedin-1.php%3FlType%3Dinitiate%26lResponse%3D1",oauth_signature_method="HMAC-SHA1",oauth_signature="4w9wOVouGDsibQIpK952Qa5hd0c%3D"
            [string] => POST&https%3A%2F%2Fapi.linkedin.com%2Fuas%2Foauth%2FrequestToken&oauth_callback%3Dhttps%253A%252F%252Fkarriere.findingheads.de%253A443%252Fxing%252Flinkedin-1.php%253FlType%253Dinitiate%2526lResponse%253D1%26oauth_consumer_key%3D77en7xz71dzcr5%26oauth_nonce%3Dc817ff5679255fa456f09926883ca391%26oauth_signature_method%3DHMAC-SHA1%26oauth_timestamp%3D1600935936%26oauth_version%3D1.0
        )

    [error] => OAuth callback URL was not confirmed by the LinkedIn end-point
    [success] => 
)


LINKEDIN OBJ:

LinkedIn Object
(
    [callback:protected] => https://karriere.findingheads.de:443/xing/linkedin-1.php?lType=initiate&lResponse=1
    [token:protected] => 
    [application_key:protected] => 77en7xz71dzcr5
    [application_secret:protected] => PXXuzn8T6fDmlCgu
    [response_format:protected] => xml
    [last_request_headers] => Array
        (
            [0] => Authorization: OAuth realm="http%3A%2F%2Fapi.linkedin.com",oauth_version="1.0",oauth_nonce="c817ff5679255fa456f09926883ca391",oauth_timestamp="1600935936",oauth_consumer_key="77en7xz71dzcr5",oauth_callback="https%3A%2F%2Fkarriere.findingheads.de%3A443%2Fxing%2Flinkedin-1.php%3FlType%3Dinitiate%26lResponse%3D1",oauth_signature_method="HMAC-SHA1",oauth_signature="4w9wOVouGDsibQIpK952Qa5hd0c%3D"
            [1] => Content-Type: text/plain; charset=UTF-8
        )

    [last_request_url] => https://api.linkedin.com/uas/oauth/requestToken
)