Gmail gives me an error, need help

Hello guys, im trying to add a gmail account on "Check email from other accounts" but it gives me an error:

" Server denied POP3 access for the given username and password.
Server returned error: "[AUTH] Web login required: https://support.google.com/mail/answer/78754"

Do you guys know where could be an issue?

the answer for your question is in the google support link that you copy/pasted, so check your user/pass and check the POP or Imap servers details

Try to change your IP address

Could something be changing your IP address, like a VPN? Google sees an IP with your connection, and if that changes, it will mess things up.

4 Best way to fix Gmail error-
1. Open the Gmail app again
The first thing you can try is to reopen the Gmail app on Android. Open the multitasking menu on Android, completely remove the app and try to open it again. If the problem persists, move on to the next troubleshooting method.

2. Restart the phone
A simple restart of the phone can fix some of the annoying system and app related issues on the Android phone. Press and hold the power button on the side and select Restart.

3. Exit the beta program
Google runs a beta Program for the company’s most popular apps. If you’ve joined such a program for the Gmail app, it is time to exit from the Play Store. Follow the steps below.

Step 1: Open the Play Store on the Android phone.

Step 2: Find Gmail and open the app description.

Step 3: Scroll down and look for an option to exit the beta Program on the phone.

Now go ahead and install the latest stable version from the Play Store.

4. Update Gmail
The unexpected stop of Gmail may be due to the bad build on the phone. Google will quickly fix critical issues with the following update of the app.

-Go to the apps and games menu
-Update menu
-Open the Play Store on the phone and go to the My apps and games menu. This is where you can find any remaining updates on the apps. Find Gmail in the list and update the app to the latest version available.

Greeting,
Rachel Gomez