Adding text to PDF and having it stay as its own independent editable element?

Hi.

In my line of work, I sometimes need to fill out non-fillable PDFs (application forms) which don't have fancy modern digital forms and are designed to be printed out and filled by hand.

It's quite cumbersome in Acrobat, but adding text digitally to fill out these PDFs out is still way better than printing it out and writing by hand.

I'm noticing though that sometimes when I add new text on top of existing elements (like multiple lines of my own text overlaying existing multi-line underlines for where you write stuff), later when I come back to re-edit my added text, the edit boxes have now all changed where it's combined my text with the existing elements on the PDF in a single edit box, so the formatting / editability of my text is ruined and I have to start all over again!

How on earth can I add text in Acrobat and ALWAYS keep it as its own separate text box elements when I come back and edit it in Acrobat? Is there a function to keep certain elements fixed and noneditable, and then I can add my own extra stuff to it without changing the original stuff?

Thanks for your help!

Glen