That’s not necessary. All someone has to do is open a second tab and check their ping list to see if the comment posted.
If it’s not there, then they can hit the post button again.
Sometimes it’s just a matter of someone’s computer hiccuping, or they accidentally double click, or sometimes there’s a weird message from FR about Proxy errors, but that often happens with large ping lists. Then it’s good to check on another tab to see if the comment posted.
No need to wait so long before retrying. Sometimes just checking to see if it posted will avoid multiple posts.