Magento 2 message: "The authenticity of the gateway response could not be verified." Error Authorize.net

Question

I am facing below error while doing payment by Authorize.net Sandbox Account

"The authenticity of the gateway response could not be verified."

I tried to resolve this by creating new Transaction Key and Signature Key but nothing happened.

While Checkout Order is not placed and gives above error but in Authorize.net they show Unsettled Transaction, check below:

Payment log gives success message

    [2019-07-08 10:03:59] main.DEBUG: array (
  'request' => 
  array (
    'payload_type' => 'createTransactionRequest',
    'merchantAuthentication' => 
    array (
      'name' => '8s92nHBP64',
      'transactionKey' => '438Fea4rnT835S33',
    ),
    'transactionRequest' => 
    array (
      'transactionType' => 'authOnlyTransaction',
      'amount' => '500.50',
      'payment' => 
      array (
        'opaqueData' => 
        array (
          'dataDescriptor' => 'COMMON.ACCEPT.INAPP.PAYMENT',
          'dataValue' => 'eyJjb2RlIjoiNTBfMl8wNjAwMDUyRTg2NjI4RTM1REJERTlBRkVGRTA2MjY4MTg3RkQ1RkRFMUE0NzRCODBCMTk3N0MwOTIyM0E1NTExN0NFNTdDRTY2NDgyNUQ4RjAyQ0VFQjJBM0MwMEUwMTdFMTkyRTZFIiwidG9rZW4iOiI5NTYyNTgwMjM1NjM1OTM3NDAzNTAxIiwidiI6IjEuMSJ9',
        ),
      ),
      'solution' => 
      array (
        'id' => 'AAA102993',
      ),
      'order' => 
      array (
        'invoiceNumber' => '000000017',
      ),
      'poNumber' => NULL,
      'customer' => 
      array (
        'id' => NULL,
        'email' => '[email protected]',
      ),
      'billTo' => 
      array (
        'firstName' => 'bewdfjb',
        'lastName' => 'bb',
        'company' => 'nbn',
        'address' => '86 Jones Common, Greenview, FK8 1LD',
        'city' => 'Indianapolis',
        'state' => 'Greenview',
        'zip' => 'FK8 1LD',
        'country' => 'GB',
      ),
      'shipTo' => 
      array (
        'firstName' => 'bewdfjb',
        'lastName' => 'bb',
        'company' => 'nbn',
        'address' => '86 Jones Common, Greenview, FK8 1LD',
        'city' => 'Indianapolis',
        'state' => 'Greenview',
        'zip' => 'FK8 1LD',
        'country' => 'GB',
      ),
      'customerIP' => '27.109.19.234',
      'userFields' => 
      array (
        'userField' => 
        array (
          0 => 
          array (
            'name' => 'transactionType',
            'value' => 'authOnlyTransaction',
          ),
        ),
      ),
    ),
  ),
  'response' => '{"transactionResponse":{"responseCode":"1","authCode":"R8Y1BD","avsResultCode":"Y","cvvResultCode":"P","cavvResultCode":"2","transId":"40034332102","refTransID":"","transHash":"","testRequest":"0","accountNumber":"XXXX4444","accountType":"MasterCard","messages":[{"code":"1","description":"This transaction has been approved."}],"userFields":[{"name":"transactionType","value":"authOnlyTransaction"}],"transHashSha2":"80F1E27E02A4F3AD91851A4828EDE9CDF6728A5493556AE3228A8D57245D85693D987738705E273E883A2C2A80ED73230CE4B7C399006BC3929239AD845DC65B","SupplementalDataQualificationIndicator":0},"messages":{"resultCode":"Ok","message":[{"code":"I00001","text":"Successful."}]}}',
) [] []

Please help me!

Answer 1

As I figured it out, everything configured correctly and Payment Gateway is also working, The only thing is it didn't worked in sandbox mode and when I switched to production mode, it worked.

Answer 2

This is caused by a Magento/Authorize using the wrong key to encode/decode the hash, so regenerating a new key and but make sure to check "Disable Old Transaction Key Immediately" and "Disable Old Signature Key Immediately" while generating the new keys in Authorize.net admin

    if (!$valid && $amount > 0) {
        $hash = $this->{$generateFunction}(
            $storedHash,
            $this->config->getLoginId($storeId),
            '0.00',
            $transactionResponse['transId'] ?? ''
        );
        $valid = Security::compareStrings($hash, $transactionResponse[$hashField]);
    }

    ....

    return $this->createResult(
        false,
        [
            __('The authenticity of the gateway response could not be verified.')
        ],
        [self::ERROR_TRANSACTION_HASH]
    );

Take a look at https://stackoverflow.com/questions/56490220/magento-2-3-1-authorize-net-payment-method-the-authenticity-of-the-gateway-res