Hi, I am experiencing the same error when using the sandbox endpoint https://api-3t.sandbox.paypal.com/nvp. Last week I received an email from PayPal saying this: We conducted a round of testing to emulate the upgraded security experience for supporting ONLY TLS 1.2 so that merchants can understand the areas of their integration that still require work. Our records indicate this Merchant Security Testing impacted you. Therefore, you will need to update your PayPal integration(s) to TLS1.2 PRIOR to June 2018 to avoid further service interruption. For more detailed information on upgrading to TLS1.2, please refer to the TLS 1.2 and HTTP/1.1 Upgrade site. How can I test to see if my system supports TLS 1.2 if the sandbox is unavailable? Thank you
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