No control connection for command:success

I am getting No control connection for command:success on trying to connect to ftp after entering correct username and password

connect_from_port_20=Yes
@vipultyagi29 Have you done this in config file?

Nope. Need to be done??

@vipultyagi29 Should do this first and try

Yes it is done. Still getting same error

refer -> Ftp Login Failed

Actually none of the solution mentioned worked for me. If I set run_as_launching_user=NO, server refuses to start

Same here. I cannot run vsftpd if that launching_user is set to no.