Previous awarded premiums with ESA not yet being paid with UC

Late applying to migrate from ESA had a home visit ,now in regular phone appointments with DWP . Being paid UC but they keep telling me this is a n. claim so the disability premiums I had don’t count so theyre neing assessed and one agent saif I might have to send sick notes in .
I have a mental illness which is not going to go awayand take medication .
Is it correct that I am being treated as a new claimant ?
The stress and
worry is making me ill .
I had to go to tribunal to get my ESA reinstated years ago ,cant face that again .