Saving while writing with Apple Pencil on PDF in files app.

I have been trying to use my Apple Pencil while writing on PDF documents in files. If I write something, (or sometimes I haven’t even started writing yet) it will reload the file, and all of my work will be gone. I have tried saving frequently to prevent a lot of work being deleted, but even then, that takes too long. So, I need it to be able to not reload. This is on iPad Air 13 inch with Apple Pencil pro. The software update is at 18.6.2.