changed .php file and got locked out, no ftp

Trying to fix that without going directly to the server would be like trying to repair an engine without lifting the hood. The site owner should have access, or maybe the host does those kinds of things for people.

If you don’t have FTP access you might have soem file system and editing available through your websites hosting control panel. That’s the first place to look.

If you don’t have that either, then you are not going to be able to fix this yourself, and you’ll need to talk to your hosting company to see what they can do to help.