i have never done that, generally you only delete the content of the public_html folder.
staff may need to redo that for you as its a system folder for your website.
however you can try this (but i cant promise it will work)
go to my files > domains > your domain folder in the right side you would see the 3 dots, choose new folder
then add public_html to there and create the folder.
inside the public_html folder you should add a new cgi-bin folder as well.
be sure both new folders have 755 for a chmod value.
in your new public_html folder you might need to create a new .htaccess and index.html index.php file.
unless you already have those backed up someplace.
as stated this might work or it wont its up to you if you want to try it.
alternatively you can wait for staff to respond and fix it for you.