If you have setup a redirect using the Redirects icon in cPanel, it may not always work. The reason for this is that the redirect icon will create the rule for the redirect in the .htaccess, but it will place this new rule at the bottom of the file. So if you have any other redirects happening ahead of the new rule that conflict with the new rule, then the new redirect just won’t work.
To fix this, after you have created the redirect, you need to find it in your .htaccess. Move the lines to the top of the .htaccess file, then re-save it, and now the redirect should work without any issues.