Locating server

People are having issues joining my server. For some people when they try to join it just says locating server forever. They are never able to connect just locating server for hours

 

Is the whitelist activated?

 

No, some people are able to join but some get stuck on locating server. If they join on an alt it then works for hyphen for some reason

 

Is everyone on your server using the right version?

 

Also whenever someone tries to join, but it doesn't work, is there a message in the terminal?

 

/ver check version. if your server loacl ip
anyone can join if whitelist on anyone can't join but name in whitelist and local ip