UC And LCWRA

Sorry this is a long one but I’d appreciate any help or advice.

So in Aug my husband, who was in receipt of ESA in the Support group, received his letter to migrate to UC. We are to receive our first UC payment on the 14th of November. He hasn't worked since about 2013. I also haven't worked for nearly 20 years. I had to leave my employment with many health issues, but I received DLA, now PIP, for those disabilities, and I was put on my husband's claim when he eventually had to leave work because of his disabilities. He received ESA with LCWRA, which he will now loose because he no longer receives ESA. We were told at the time I couldn’t receive  LCWRA as only one of the married couple could receive  LCWRA, but I WAS NOT required to hand in any Fit Notes.
On the 31st of December this year, my husband officially retires, so this migration has only been for about 6 weeks, but there was nothing we could do about it, it was just bad timing.
I don’t officially retire until May 2028. As part of our UC claim, which I will still receive, they are asking me to supply them with Fit Notes, but I don’t understand why, when I have never had to do this before. My stress levels are above and beyond, as one of my disabilities is Autism, and I just can't cope or deal with this any more. I have tried to get answers from them on the phone, but every time I speak to someone, I get different answers