HEX Color does not register or change

[claudia_dtr]

I've tested other HEX Codes and there doesn't seem to be an issue, but when I enter HEX #: 6595ff, the color shows up on the  Color Picker box, but won't adjust the color to the selected graphic.  It will either revert back to the last color or just "accept the color" but not change the color.  

I have already reselt color preferences, and still nothing.  I'm stumped as there are no "out of gamut" warnings or anything.  I entered the code manually, entered the codes in RGB manually without entering the HEX code and nothing. 

I have no other issues with other HEX Codes, just THIS code.  Can anyone help?

[Monika Gause]

You are working in a CMYK file. What business does HEX have in this?