key edit problem with echostar

Greetings to All:confused

Forgive me if this has been asked before.
I have trawled the forums, but without success.

I have an echostar dsb-808 2ci vi with mr/1.055.
The edited keys do not seem to be saved.

This is what I do:
Go to a FTA channel
Go to the menu - mr-cas key edit
Go to nagra
Go to 7100, then 00
Enter the new keys
Exit back out to the FTA channel
Go to polsat - does not clear

When I look again at the edited keys, they have changed back to the pre-edited version.

I am obviously doing something wrong.
Please can you help.

Thanks in advance,
chriss :confused