Query failed: Failed to establish a database connection

I have success with database connection before with the same user connection but now I don't know why I keep getting this error when try to connect on google sheet.

Query failed: Connection to mysql database sagiserp_v2 at sagisepr.com failed with user sagiserp_google from ip 58.8.215.142, 107.178.195.201 Failed to establish a database connection. Check connection string, username and password.

I also tried another user/pass of my database but still not work

all google's ip address is added to whitelist on my database.