Rdp BruteForcing Not Locking Out Account

Hello,

I am currently testing rdp bruteforcing with several tools such as, crowbar,Hydra, and Ncrack. The problem I am having is that none of the tools seem to be locking out the account I am targeting. I tested if the account was actually locking out by manually hand jamming it and it locked. Has anybody had similar issues ? I have read many posts and followed guides on the tools and don't think I am using them wrong. It is on a windows domain.