I'm trying to do a full reset on my C7 hub but I keep getting a message that the hub has a subsciption. My C8 hub is the only hub that has a remote admin subscription. I've already done a zigbee radio reset, z-wave radio reset, and soft reset on the C7 hub and I de-registered the C7 hub. It still refuses to allow me to do a full reset.
Have you submitted a case using the following form for subscription issues?
Remote Admin is applied to the entire account, so unless you had two different accounts, this would actually not be the case. I think it still lets you de-register and full reset if it's not set as the hub that "owns" the subscription (EDIT: nevermind, Remote Admin is tied to the account), so that must additionally be the case for you. Support should be able to address this at the link above (EDIT: nevermind, the steps you've performed are effectively the same result, so that isn't necessary) -- but that would explain it.
BTW, I don't see a Matter reset above, so if you've used that and want to reset it too, I'd look at the doc again for those steps.