I've written a page of text in Impress a fumble & I've lost it all

I don’t think there’s a solution but if someone could explain what happened?

I’ve just written a slide with a Title and a series of bulleted texts, I then wanted to adjust the format, I think maybe some text was highlighted and maybe I fatally touched delete. What surprised me was that undo & redo didn’t help in fact I eventually even lost the Title.

I may in future prepare my text with a text editor

Any tips?

You have already submitted the desired explanation yourself.
You wrote something in an open file and then deleted it. That’s how I understood it.

If you are working with a text editor in the future, make sure that you do not delete the content.

Future: After opening a file, save it immediately under a desired name. Then the more often in between click again on Save. Good luck!

i just wanted to know why my delete wasn’t undo-able

It might be a bug; if you have reproducible steps how to get non-undoable removal, please file it to bug tracker. Thanks.