Request for payslips from L’ Assurance Maladie

Hi, I sent in my ID and photo etc to L’assurance Maladie after Easter and have received a letter back asking for a copy of my contrat de travail and last three payslips etc.- which I find a bit confusing given that I am signing up to be a ME.

Also I note that the letter is not using the same spelling of my name as what I am registered with and was quoted on the first letter also my social security number looks a bit like a ‘dummy’ one. it is definitely not my temporary one that is on my first letter from l’assurance maladie nor URSSAF.
I have had a fiscal number for a number of years in order to pay tax d’habitation etc so maybe they have somehow linked my request to my existing impots number…...

ALSO-  moving forward I am in discussions with my UK employer to work for them under an arrangement with an external company under a service called ‘Employer of Record’ - they act a bit like a portage company so if this proceeds it looks like I won’t be needing to use my Micro Entrepreneur set up. I guess I will look to close that down but not sure when best to do that. When I registered for my ME Siret number I stated that I would be starting to work as of the 1st May 2024 but that has not occurred yet as I have not moved to France yet.  How do you recommend I move forward on this one?

I also assume once I start generating payslips with the portage company I can submit the requested paperwork to l’assurance Maladie as this latest letter requests.- do you agree?