This is the ASK problem, which is by far one of the STUPIDEST things Motorola ever did, in some ways it's even more stupid than when they "toolproofed" the Jedi radios to keep leaked lab software from being used with them.
With the ASK problem, Advanced System Key enabled, if you don't have the relevant Advanced System Keys in your programming computer, you can't edit the radio's contents and be able to save them to the radio, even if you only edit conventional data. Even if there's no trunking data in the radio, the presence of the ASK demands that the keys have to be in your programming computer for the trunked system(s) that used the ASK in question.
What this means is that radios can NOT have their trunking data removed from them unless they're removed from a computer that has the valid ASK keys loaded into it.
Which is precisely the OPPOSITE of what a system administrator should want to happen, from the perspective of system security.
Imagine...a bunch of radios get sent to public auction because they're out of date. But they still have the trunked system data in them and can still interact with the system....but they can't be deprogrammed!
Really, it IS that stupid.
Yes, there are ways to remove the ASK from the radio. I know of at least two. Neither of which I'm going to talk about and neither of which I can provide to anybody for any reason.