[Koha] Unable to update form

[Stew Wilson]

Hi everyone,
I am very new to Koha - and this seems like a question which is often
asked, but I have not yet found a comprehensible response!

I tried editing my own MARC framework.  This worked well, until I
accidentally deleted a tag that I wanted to keep.  So, I added it as a new
tag, and copy-pasted the information from the existing tag in the default
framework.  This added fine and looks no different from the information in
the default framework.  However, when I now try to input information into
that tag as I'm adding a new record, I am unable to enter anything in the
box.  The cursor is there, but nothing is entered in the field.

I have a feeling that this something to do with authorities - but I
wouldn't know where to start!

Is someone able to point me in the right direction?

Thanks,
Stew