Klaviyo can't connect to your Magento 2 store (OAuth handshake error). Here's how you can fix it:

• Check accessibility: Make sure these Magento 2 URLs are reachable: /oauth/token/request & /oauth/token/access. Use tools like Postman or curl to test.
• Review Klaviyo docs: Double-check the Klaviyo documentation you used for specific troubleshooting steps.
• Enable Bearer Tokens (Magento 2.4.6+): In Magento admin, go to Stores > Configuration > Services > OAuth > Consumer Settings. Set "Allow OAuth Access Tokens..." to Yes. Save changes.
• Look for firewall/security restrictions: Ensure nothing on your server is blocking Klaviyo's access to those URLs.

Let me know how it goes, looking forward to your reply!

How can i test this?

• Check accessibility: Make sure these Magento 2 URLs are reachable: /oauth/token/request & /oauth/token/access. Use tools like Postman or curl to test.

Using Postman:

1. Open Postman: Launch the Postman application on your computer.
2. Create a GET Request: Click the "GET" button to initiate a GET request.
3. Enter the URL: In the URL bar, paste the first endpoint URL: https://syour-magento-store.com]/oauth/token/request (replace "ayour-magento-store.com]" with your actual Magento store URL).
4. Send the Request: Click the "Send" button.

Expected Response:

• If the endpoint is accessible, Postman should display a response code in the 200 range (e.g., 200 OK). This indicates a successful connection.
• The response body might contain additional information depending on your Magento configuration.

Repeat for Second URL:

1. Repeat steps 2-4, replacing the URL with the second endpoint: https://tyour-magento-store.com]/oauth/token/access.

Getting this error while trying it on postman

base_url/oauth/token/access

oauth_problem=%22oauth_consumer_key%22+is+required.+Enter+and+try+again%2C+%22oauth_signature%22+is+required.+Enter+and+try+again%2C+%22oauth_signature_method%22+is+required.+Enter+and+try+again%2C+%22oauth_nonce%22+is+required.+Enter+and+try+again%2C+%22oauth_timestamp%22+is+required.+Enter+and+try+again