mySQL Replication Error. login incorrect

I have been trying to setup MySQL replication for the first time. I read many articles and it appears very easy, but I guess I made a typo when setting up the slave. I am getting the following error in the error log.

2016-10-02T14:29:45.479004Z 1 [ERROR] Slave I/O for channel '': error connecting to master 'abcd123@server3:3306' - retry-time: 60 retries: 2628, Error_code: 2003

I looked it up and "error 2003" said that the user cannot login to the master I guess. Which is correct cause server3 is incorrect. That was my typo. I have 3 servers

Server1 Master mysql
Server2 Slave mysql
Server3 web server.

So server3 is incorrect. I tried to change the login using the command.

STOP SLAVE;
CHANGE MASTER TO MASTER_HOST='10.0.0.1',MASTER_USER='abcd123',MASTER_PASSWORD='PASSWORD',;
START SLAVE;

But I am still getting the error above.