I assume that your CPAM has the letter from the DWP which terminated your rights to an E106 in (presumably) '06. Did you keep a copy? I had the same thing, and explained this to them, and that they had had my letter x years ago. Within a week, the confirmation that both of us were "in" arrived. I was already in CMU so it's slightly different, but maybe this is what's happened?
As a CMU subscriber, you have "ayant droit" on the basis of your o/h's acceptance, but they need to be sure you're not entitled to any kind of E form.
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