Error sending email from nodejs Application

gistfile1.txt

Server is up on port 3000
(node:5931) UnhandledPromiseRejectionWarning: Error: Bad Request
    at Request.http [as _callback] (node_modules/@sendgrid/client/src/classes/client.js:124:25)
    at Request.self.callback (node_modules/request/request.js:185:22)
    at emitTwo (events.js:126:13)
    at Request.emit (events.js:214:7)
    at Request.<anonymous> (node_modules/request/request.js:1161:10)
    at emitOne (events.js:116:13)
    at Request.emit (events.js:211:7)
    at IncomingMessage.<anonymous> (node_modules/request/request.js:1083:12)
    at Object.onceWrapper (events.js:313:30)
    at emitNone (events.js:111:20)
    at IncomingMessage.emit (events.js:208:7)
    at endReadableNT (_stream_readable.js:1064:12)
    at _combinedTickCallback (internal/process/next_tick.js:138:11)
    at process._tickCallback (internal/process/next_tick.js:180:9)
(node:5931) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 1)
(node:5931) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.