When switching to a different subscription it is best to uninstall completely via Control Panel. Then run the MCPR cleanup tool listed under Useful Links above and reboot immediately.
Then install the new one from your new online account or the CD if that's how you bought it, as this is now a completely different subscription.
You could also try the subscription repair tool: HERE.
If you prefer French speaking then alter your country to France at the top right of those pages (or any other you prefer).
There is free telephone support but your best choice most likely would be online chat.
Ok this really 1 for customer service They are linked to in useful links tab above. Best to ask there.
What does the subscription area say in the Security centre opening page? Active or what
Or do what Peter says he posted while I was thinking