my website doesn't work with www

It has to do with your redirect. Have you check your cpanel setting for your domain redirect?

its working It was DNS issu

you don’t need the archaic & awkward ‘www’ subdomain. As long as it redirects for anyone who insists on typing it, you’re better off without it.

If you feel you need to use ‘www’ as your primary address, you can specify it in the home & site url settings on the Settings->General page in admin.

https://codex.www.ads-software.com/Changing_The_Site_URL