Trying to implement NodeJS Gmail API example - node.js

Question

I am trying to get the NodeJs Gmail API Quickstart example working. At first, I was able to get the example running and receive an out put that looked like this.
INBOX
SPAM
ETC ...
I made a few changes after so that I could see messages, etc. Once that happened I started getting the following error after the prompt (It was working prior).
Authorize this app by visiting this url: https://accounts.google.com/o/oauth2/v2/auth?access_type=offline&scope=https%3A%2F%2Fwww.googleapis.com%2Fauth%2Fgmail.modify&response_type=code&client_id=***&redirect_uri=***
Enter the code from that page here:
I get this error code
Error retrieving access token GaxiosError: invalid_grant
at Gaxios.<anonymous> (C:\***\node_modules\gaxios\build\src\gaxios.js:73:27)
at Generator.next (<anonymous>)
at fulfilled (C:\***\node_modules\gaxios\build\src\gaxios.js:16:58)
at processTicksAndRejections (internal/process/task_queues.js:97:5) {
response: {
config: {
method: 'POST',
url: 'https://oauth2.googleapis.com/token',
data: 'code=***client_id=***&client_secret=***&redirect_uri=http***=authorization_code&code_verifier=',
headers: [Object],
params: [Object: null prototype] {},
paramsSerializer: [Function: paramsSerializer],
body: 'code=***&client_id=***&client_secret=***&redirect_uri=***&grant_type=authorization_code&code_verifier=',
validateStatus: [Function: validateStatus],
responseType: 'json'
},
data: {
error: 'invalid_grant',
error_description: 'Malformed auth code.'
},
headers: {
***,
***
},
status: 400,
statusText: 'Bad Request'
},
config: {
method: 'POST',
url: 'https://oauth2.googleapis.com/token',
data: 'code=***&client_id=***&client_secret=***&redirect_uri=***=authorization_code&code_verifier=',
headers: {
'Content-Type': 'application/x-www-form-urlencoded',
'User-Agent': 'google-api-nodejs-client/3.1.2',
},
params: [Object: null prototype] {},
paramsSerializer: [Function: paramsSerializer],
body: 'code=***&client_id=***&client_secret=***&redirect_uri=***&grant_type=authorization_code&code_verifier=',
validateStatus: [Function: validateStatus],
responseType: 'json'
},
code: '400'
}
So I reverted the changes back to the original quickstart code, and I am still getting the above error. I have no idea why this is happening and would appreciate some help!

Answer 1

the taken of Gmail api expires really soon after you work with it
try to delete the credentials.json and start the script again .