PayPal future payments INTERNAL_SERVICE_ERROR when execute payment
<p>I'm using Rails 4.2, Ruby 2.2, <a href="https://github.com/paypal/PayPal-Ruby-SDK" rel="nofollow">PayPal-Ruby-SDK
</a>, PayPal sandbox</p>

<p>I can create payment, but it has <code>pending</code> status.
When I try ti <code>execute</code> it (according to documentation), I get error</p>

<p><code>INTERNAL_SERVICE_ERROR</code></p>

<p>REQUEST:
<code>Request[post]: https://api.sandbox.paypal.com/v1/payments/payment/PAY-8KG44388FJ2409934K4Q4TYY/execute
Request.body={"payer_id":"2"}   request.header={"Authorization"=&gt;"Bearer A101.pMlaF6XYq42QPcr-N6cIlwQfyeJNiNwLG6XPMsthrRT3lQ-ENCCIv1X-kFdp2C3_.7s4U_X9jF2hfHtJ-bKPzv-bbmDe", "Content-Type"=&gt;"application/json", "User-Agent"=&gt;"PayPalSDK/PayPal-Ruby-SDK 1.4.4 (paypal-sdk-core 1.4.4; ruby 2.2.4p230-x86_64-linux;OpenSSL 1.0.1f 6 Jan 2014)", "PayPal-Request-Id"=&gt;"9187f64f-bb31-43c3-878c-3b10f5bd9616"}</code></p>

<p>RESPONSE:
<code>Response[400]: Bad Request, Duration: 0.917s
Response.body={"name":"INTERNAL_SERVICE_ERROR","message":"An internal service error has occurred","information_link":"https://developer.paypal.com/docs/api/#INTERNAL_SERVICE_ERROR","debug_id":"92f7c262ba80a"}    Response.header={"date"=&gt;["Tue, 03 May 2016 10:36:46 GMT"], "server"=&gt;["Apache"], "proxy_server_info"=&gt;["host=slcsbplatformapiserv3002.slc.paypal.com;threadId=410"], "paypal-debug-id"=&gt;["92f7c262ba80a", "92f7c262ba80a"], "correlation-id"=&gt;["92f7c262ba80a"], "content-language"=&gt;["*"], "connection"=&gt;["close", "close"], "set-cookie"=&gt;["X-PP-SILOVER=name%3DSANDBOX3.API.1%26silo_version%3D1880%26app%3Dplatformapiserv%26TIME%3D1048520791%26HTTP_X_PP_AZ_LOCATOR%3D; Expires=Tue, 03 May 2016 11:06:46 GMT; domain=.paypal.com; path=/; Secure; HttpOnly", "X-PP-SILOVER=; Expires=Thu, 01 Jan 1970 00:00:01 GMT"], "vary"=&gt;["Authorization"], "content-length"=&gt;["194"], "content-type"=&gt;["application/json"]}</code></p>

<p>I was trying execute it several days but got same result.</p>

<p>I've written 2 response to PayPal technical support, but I didn't get any answers. </p>

<p>Maybe somebody knows what happened?
Thanks!</p>