InvalidSignatureException Amazon sp api

Hello, I'm trying to connect the amazon SP api and I get this exception when making a request to the api:InvalidSignatureException I've looked on the amazon site and it says: "The authentication token in the request has expired. " But I can't seem to find where in my request I'm going wrong this is my code:

public function GetInfo($url, $options)
    {
        $uri = $url;
        $apiURL = self::AMAZON_API_URL;
        $marketplaceID = self::MARKETPLACE_ID;
        $url = "$apiURL$url?marketplaceIds=$marketplaceID&granularityType=Marketplace&granularityId=$marketplaceID";
        //datetime format: YYYY-MM-DDTHH:MM:SS.SSSZ
        $accesKey = env('AMAZON_ACCESS_KEY');

        $datetime = date("Ymd\THis\Z");
        $date = date("Ymd", strtotime($datetime));
        $this->Authenticate();
       $signature = $this->GetSignature($datetime,$uri);
        $authorizationString = "AWS4-HMAC-SHA256 Credential=$accesKey/$date/eu-west-1/execute-api/aws4_request, SignedHeaders=content-type;host;x-amz-date;x-amx-access-token, Signature=$signature";



        if (!empty($options)) {
            $request = Http::withHeaders([
                'Accept' => 'application/json',
                'host' => self::AMAZON_API_URL,
                'user-agent' => 'bol-voorraad/1.0 (Language=PHP/7.2.0; platform=windows/10)',
                'x-amz-access-token' => $this->token['access_token'],
                'x-amz-date' => $datetime,

            ])->post($url, $options);
        } else {

                $request = Http::withHeaders([

                    'Authorization' => $authorizationString,
                    'content-type' => 'application/json',
                    'host' => 'sellingpartnerapi-eu.amazon.com',
                    'x-amz-date' => $datetime,
                    'x-amz-access-token' => $this->token['access_token'],
                ])->get($url);


        }
        dd($request);
        return $this->DecodeBody($request);
    }

  

 public function GetSignature($datetime, $uri)
    {
        $secretKey = env("AMAZON_SECRET_KEY");

        $date = date("Ymd", strtotime($datetime));
        $region = self::REGION_STRING;
        $service = "execute-api";
        $query = "marketplaceIds=". self::MARKETPLACE_ID ."&granularityType=Marketplace&granularityId=". self::MARKETPLACE_ID;
        $payload = hash("sha256", "");
        $credentialScope = "$date/$region/$service/aws4_request";

        //create a cannonical request
        $canonicalRequest = "GET" . "\n" .
            $uri . "\n" .
            $query . "\n" .
            "content-type:" . "application/json" . "\n" .
            "host:" . self::AMAZON_API_URL . "\n" .
            "x-amz-date:" . $datetime . "\n" .
            "x-amz-access-token:" . $this->token['access_token'] . "\n" .
            "\n" .
            "content-type;host;x-amz-date;x-amz-access-token" . "\n" .
            hash("sha256", "");


        //create a string to sign
        $stringToSign = "AWS4-HMAC-SHA256" . "\n" .
            $datetime . "\n" .
            $credentialScope . "\n" .
            hash("sha256", utf8_encode($canonicalRequest));


        $signingKey = $this->GetSignatureKey($secretKey, $datetime, $region, $service);
        $signature = hash_hmac("sha256", $stringToSign, $signingKey);
        return $signature;
    }

    public function GetSignatureKey($secretKey,$date,$region,$service)
    {
        $kSecret = "AWS4" . $secretKey;
        $kDate = hash_hmac("sha256",  $date,$kSecret, true);
        $kRegion = hash_hmac("sha256",   $region, $kDate, true);
        $kService = hash_hmac("sha256", $service, $kRegion, true);
        $kSigning = hash_hmac("sha256", "aws4_request", $kService, true);

        return $kSigning;
    }

  public function GetInventory()
    {
        $url = '/fba/inventory/v1/summaries';
        $options = null;
        $body = $this->getInfo($url, $options);


    }