Access to CPAM

I registered as a micro-entrepreneur when I arrived in France in December (from the UK), and in April I received a letter from CPAM recognising my self-employed status, and asking for my RIB, a copy of my birth certificate and a piece of identity to gain access to assurance maladie. I did this, then in June I received another letter asking for a work contract and payslips, which of course I don’t have as a micro-entrepreneur.

I was about to move from Haute-Garonne to Bouches-du-Rhône at this point, so I decided to start again with CPAM in Bouches-du-Rhône once I’d moved, and once my carte de séjour arrived (which it now has). But here they have refused to give me an appointment to try to set this up, telling me to fill in a form and post it to them, but I think the form is not for self-employed people. Could you please advise how I can re-start this process in the correct way?

I have a health issue that has now become urgent, but I assume if I go to the emergency unit I will be charged and won’t be able to get it refunded? I do still have my British EHIC card which I think would be valid, but only if I were a tourist.

Thanks in advance
Matthew