Is there a restriction on the name 'directory'? Keep getting 403

Hi,

I have a DO droplet, set up my app via Serverpilot, running a CraftCMS install. Everything has been fine, but just hit an issue. I’m trying to create a subfolder from my root called ‘directory’ so it would be accessed via domain.com/directory. However I keep getting a 403 error when trying to access this. It works fine on a local environment, but when pushed up I get the

"You don’t have permission to access /directory/ on this server.

Possible causes of this error include:

The request was forbidden by rules in the .htaccess file. The directory you requested does not have an index.html or index.php file. The permissions on the file or directory are incorrect."

message. If i rename this folder to anything else, it works.

Just a bit stumped.