Why does my tax return copy say, Do not file form not final? i filed they accepted it , now just need the copy for proof etc..

Try this method to print/download the most up-to-date version of your return by opening your return back up and printing at the Print Center, and hopefully, it will have no watermark.

NOTE:  When you open your return back up, do not make any changes in it since it's already been filed.

• Log in and go to "Your Tax Returns & Documents."  Click that line or on the word SHOW to expand that section.
• Choose 2017 tax year.
• Click on "Add a State."  (you don't really add one.  That's just to open your return back up.)
  
• After the return is open and past the blue-green screen, click in the left menu column on TAX TOOLS, then PRINT CENTER.
• Then choose "Print, save, view this year's return."
• The next screen should offer 3 options:  "Just my tax returns", or "include government worksheets (optional)", or "include government and TurboTax worksheets (optional.)"
• See if one of those PDFs has what you need without the watermark.
  

NOTE:  Do NOT use this method to open a return to make changes/edits to an already-filed return (one that has actually been mailed or efiled.)   If you later need to make changes to an already-filed return, you have to go through the formal amending process, and your return must start off exactly as originally filed.

Thanks worked perfect!

Great news!   I'm glad you got it.  Good luck.