FTP add-on won't install

I am running the 32bit version of Hass.io on my pi3 B, and I am unable to install the FTP addon to edit the config.yaml file. I wanted to use the FTP addon because the configurator add-on won’t work, and neither will the Cloud9 IDE (even with port-forwarding on my router) This is the error I found in the system log after the install button turned red on the FTP add-on installation screen:

Can't install hassioaddons/ftp-armhf:1.5.0 -> 500 Server Error: Internal Server Error ("readlink /var/lib/docker/overlay2: invalid argument").

Any help on the FTP, configurator, or Cloud9 add-ons would be greatly appreciated. It seems this configuration.yaml is pretty important, and I can’t seem to access it, despite there being several options. Thanks.