What do you mean by "PS 6"? Did you mean Photoshop CS6?
Do you have a Perpetual License or a Creative Cloud subscription?
Did you apply all the updates? What version do you see on the first line of your Photoshop Help - System Info display?
The devil is in the details
Photoshop CS 6 -
Perpetual License - paid for the software
Applied all updates
Photoshop Help Sys Info - Adobe Photoshop Version: 13.0.1 (22.214.171.124 20131024.r.34 2013/10/24:21:00:00) x64
Thanks Noel for any help yu can provide
Thanks for confirming you're up to date.
I'm sorry to keep asking you for information, but can you show a screen grab of (or describe in detail) the options you've chosen with the Fill tool (I mean the dialog you get if you choose Edit - Fill from the menu)? There are a fair number of choices there, and I'm wondering whether you've told it to do something different than you're expecting.