The color shows up on print preview, but when it prints it’s black and white. In the past it printed in color. I’m thinking I set something incorrectly by mistake. I’m using a logo from an old MS file. could that be the problem.
MS Office used to have a place on the print properties page that said color or black and white. I don’t see that on Libre. I have it set to normal print.
I have exactly the same problem. Two weeks ago I printed a document in color and yesterday the same doc will only print in b/w. Nothing changed or updated on my system in the interim. I have Windows 10 Home on a HP 15-g080nr laptop and HP Envy 4511 printer. I’m using LO Version: 6.3.6.2 (x64).
There is a hidden setting on the document that doesn’t show up anywhere in the Print dialogue. That is “convert colours to grayscale” which is found under “Tools” menu, “Options”, then under “Libreoffice” click on “Print” then look to right under “Defaults” and un-check “convert colors to grayscale”.
If that is set (checked) then nothing else you do from the Print dialogue or Printer Properties will get you color.
Simple as can be lol.
Open the printer dialog using File | Print, select your printer and click on the Properties button underneath the printer selection list. Check the settings under Device for colour selection.
If this answer helped you, please accept it by clicking the check mark 
to the left and, karma permitting, upvote it. That will help other people with the same question.
In case you need clarification, edit your question (not an answer) or comment the relevant answer.
I looked under file/print, click on Properties.Believe me I’ve tried that a million times. Under Properties there is nothing that says Device or Color. I could only find a box to check if you wanted it to print in black and white. Obviously I don’t have that box checked. My three options under Properties are lay out/paper/print shortcuts. I’ve looked under each of those headings many times. There is nothing that says Device or Color. What am I missing. Yesterday is the first time I’ve had this problem
It often comes down to this : What is your Operating System (and version), which version of LibreOffice are you using, and (in this case) what make and model of printer are you using?
My operating system is Windows 10 version 1903. I purchased the computer in Dec 2019. The printer is a HP pavillion One Envy 4520. The printer works well when I print from my old Windows 7 and it was printing well from my new computer until recently… Best Buy installed Libre over the phone for me about 2 weeks ago. It was printing in color fine until last week. That is why I think I changed something by mistake. It went into protective mode recently (I can’t remember why and I changed it back to regular --I don’t remember how). I’m 68. Technology is not my first love.
I send Shirley’s comment because this is the same thing happening to me…I have tried everything mentioned in above suggestions (at least the ones I understood) and still cannot print in color. I guess I’m done
Is one of your colour inks depleted? Printer might then default to print in B&W.
If ink levels OK then read the manual to find out how to reset your printer. Often for HP it can be just pulling the plug out of the wall while the printer is switched on and waiting 15 seconds before plugging it back in and restarting. Cheers, Al
Ink is ok for both and I did unplug and plug back in and still printing in black and white…test pages have color…yesterday I deleted Librea and installed it again and still b/w
You might have to uninstall the printer drivers, restart the computer and install new ones from HP site, see Solved Envy 4520 or Bleeping computer