Server error: `POST http://repov2.businesscomm.elsapp.local/get/siteimages` resulted in a `502 Proxy Error` response: 502 Proxy Error

Proxy E (truncated...)
#0 /var/www/buco/fo/master/app/vendor/guzzlehttp/guzzle/src/Middleware.php(66): GuzzleHttp\Exception\RequestException::create(Object(GuzzleHttp\Psr7\Request), Object(GuzzleHttp\Psr7\Response))
#1 /var/www/buco/fo/master/app/vendor/guzzlehttp/promises/src/Promise.php(203): GuzzleHttp\Middleware::GuzzleHttp\{closure}(Object(GuzzleHttp\Psr7\Response))
#2 /var/www/buco/fo/master/app/vendor/guzzlehttp/promises/src/Promise.php(156): GuzzleHttp\Promise\Promise::callHandler(1, Object(GuzzleHttp\Psr7\Response), Array)
#3 /var/www/buco/fo/master/app/vendor/guzzlehttp/promises/src/TaskQueue.php(47): GuzzleHttp\Promise\Promise::GuzzleHttp\Promise\{closure}()
#4 /var/www/buco/fo/master/app/vendor/guzzlehttp/promises/src/Promise.php(246): GuzzleHttp\Promise\TaskQueue->run(true)
#5 /var/www/buco/fo/master/app/vendor/guzzlehttp/promises/src/Promise.php(223): GuzzleHttp\Promise\Promise->invokeWaitFn()
#6 /var/www/buco/fo/master/app/vendor/guzzlehttp/promises/src/Promise.php(267): GuzzleHttp\Promise\Promise->waitIfPending()
#7 /var/www/buco/fo/master/app/vendor/guzzlehttp/promises/src/Promise.php(225): GuzzleHttp\Promise\Promise->invokeWaitList()
#8 /var/www/buco/fo/master/app/vendor/guzzlehttp/promises/src/Promise.php(62): GuzzleHttp\Promise\Promise->waitIfPending()
#9 /var/www/buco/fo/master/app/vendor/guzzlehttp/guzzle/src/Client.php(131): GuzzleHttp\Promise\Promise->wait()
#10 /var/www/buco/fo/master/app/libraries/Rest/Rest.php(31): GuzzleHttp\Client->request('POST', 'http://repov2.b...', Array)
#11 /var/www/buco/fo/master/app/libraries/Repository/Repository.php(56): Libraries\Rest\Rest->request('POST', 'http://repov2.b...', Array)
#12 /var/www/buco/fo/master/app/helpers/Image.php(52): Libraries\Repository\Repository::getImage(-1, 'baremekilo.jpg', Array, 'images')
#13 /var/www/buco/fo/master/app/helpers/Image.php(28): Helpers\Image::getImage(-1, 'https://repo.bu...', 'images', 590, 264)
#14 /var/www/buco/fo/master/app/views/shared/contentListNews.phtml(121): Helpers\Image::getEflContentImage(NULL, 'https://repo.bu...', 590, 264)
#15 [internal function]: unknown()
#16 [internal function]: Phalcon\Mvc\View\Engine\Php->render('/var/www/buco-s...', Array, false)
#17 [internal function]: Phalcon\Mvc\View->_engineRender(Array, 'shared/contentL...', false, false)
#18 [internal function]: Phalcon\Mvc\View->partial('shared/contentL...', Array)
#19 /var/www/buco-shared/fo/sites/000055/html/app/views/index/contentListNews.phtml(68): Phalcon\Mvc\View\Engine->partial('shared/contentL...', Array)
#20 [internal function]: unknown()
#21 [internal function]: Phalcon\Mvc\View\Engine\Php->render('/var/www/buco-s...', Array, true)
#22 [internal function]: Phalcon\Mvc\View->_engineRender(Array, 'index/contentLi...', true, true, NULL)
#23 [internal function]: Phalcon\Mvc\View->render('content', 'contentListSimu...')
#24 /var/www/buco-shared/fo/sites/000055/html/public/index.php(48): Phalcon\Mvc\Application->handle()
#25 {main}