Thanks to Brexit, I've got 30 days to leave my home in France

I have 30 days to leave my home thanks to Brexit. our local prefecture, which last week wrote to us to tell us that we had 30 days to leave the country. The reasons they gave is that there was no proof that James is self-supporting (we were not made aware of any missing information from our application – if we had we’d have provided it) and that my business does not make enough. Between us we need to prove that we have €1175.00 per month to live on. The feeling of panic I got from the moment I opened those letters is still with me now. It sits in the pit of my stomach as a constant reminder of the nightmare we are now living.