Thank you all for your replies. I’m afraid the nearest Apple shop is about 60 miles away. I have asked Apple on line, but as yet no reply.
Crazy H, apart from this blip, OneNote has been until now, the best Note book I have ever used. When I started using it, I found that guides were mainly aimed at laptops rather than iPads, so I tried to work it out myself - probably my first mistake. I think of it (possibly incorrectly!) as a filing cabinet which has files in it for an infinite number of topics, and then sheets of paper for all your notes. OneDrive is a separate Ap and is the place that backs it all up and transfers it to the Cloud for retrieval.
Footnote to this, I have dusted down a ten year old laptop which I never use, but keep for emergencies. I have saved One Note and OneDrive on to it and also copied it onto an elderly hard drive. All this for information which is of no interest to anyone but me, and would certainly be of no use to anyone but me. My family think I’ve lost the plot, but I regard it as an antidote to wall to wall football!