Controller/Adminhtml/FastlyCdn/Configuration/CustomerInfo.php
public function execute()
    {
        $result = $this->resultJsonFactory->create();
        try {
            $customer = $this->api->getCustomerInfo();

            if (!$customer) {
                return $result->setData(['status' => false]);
            }

            return $result->setData([
                'status'    => true,
                'customer'  => $customer
            ]);
        } catch (\Exception $e) {
            return $result->setData([
                'status'    => false,
                'msg'       => $e->getMessage()
            ]);
        }
    }
public function execute()
    {
        $result = $this->resultJsonFactory->create();
        try {
            $customer = $this->api->getCustomerInfo();

            if (!$customer) {
                return $result->setData(['status' => false]);
            }

            return $result->setData([
                'status'    => true,
                'customer'  => $customer
            ]);
        } catch (\Exception $e) {
            return $result->setData([
                'status'    => false,
                'msg'       => $e->getMessage()
            ]);
        }
    }
Checking service details

@return \Magento\Framework\Controller\Result\Json