Hi, my name is Ryoung! And im having trouble with the dwp/seetec pluss

Hi there, i have been on universal credit since august 2019 and have never done a wca however the job center are saying that not only did i do one but that im fit for work, however i did not do any assessment, they are also trying to force me to look for work despite being signed off sick (open ended fit note no date to return to work on it) for the long term, i have been told that i 'was' able to contest it and i did try (my challenge was stopped due to covid), is there anyway to trigger an assessment to actually take place, also i was placed on the restart work scheme with an 'advisor' (im loathe to call them that, more lile a bullying, harrasing jobswortg with nothing better to do) that does not do anything other than send me harrasing phone calls and txt messages and offers no support for anything. Is there anything i can do about them? My mental health (undiagnosed eupd, pschopathy, adhd and autism) has suffered needlessly throughoit the entire ordeal!