Sir,
Panel was working fine but suddenly it stop login.
We restart service cwpsrv but issue remain same.
when we enter user = root and its password, same login screen appear again without any error.
root password working fine over putty ssh.
kind request to guide in to matter.
regards,
is this admin or user panel, if you are using special characters try to change the password from the command line and set it to something without special characters
https://www.random.org/passwords/?num=5&len=8&format=html&rnd=new