ESA DWP offical error

Hello really need some help new member so please bare with me.

I received a inheritance informed DWP I was in support group for ESA claim was put as credits only. Fast forward to a few months later I move to a different local authority and still inform DWP ESA as I also have a PIP claim. Everything fine fast forward to November 2021 I inform DWP my savings have dropped below threshold to be put back into payment. They send me a form to complete which I did with receipts statements and everything and I returned before due date of 20th December. Fast forward to march I start getting worried and call them to ask what is happening they say its still with DECISION maker so I left it Fast forward to today I get a call saying there has been a offical error and I should of been advised to claim universal credit so I will need to claim Universal credit. I have done this and am now worried I will not see any backdated money from 29th November 2021 to 8th of April 2022. They said I would get a letter and I need to update the journal telling them esa made a error but I'm worried I will be expected to look for work or provide sick notes until I'm assessed under Universal credit. I'm just so upset and down and I feel like DWP will now make my life hell I also could have claimed council tax benefit and I know that won't get back dated. UNIVERSAL ARE ALREADY asking me about what work I can do and to go there for a ID APPOINTMENT I have asked them to do it by phone or email as I'm just too ill to go but I bet they will ignore me I'm so sad

Thank you for your reply i really appreciate it.

The lady on the phone said it was because the dwp should not have given me the income form to fill in when I told them my savings had dropped below the threshold which I could be put back into payment. I should have been told to claim universal credit instead of them doing a capital decision through ESA . instead I was given the form to complete did so sent it back and have been waiting for a decision for months and hammering the little savings I did have left on rent and bills. Which I don't mind as long as they are paid but I see it as I have used savings I could have had even if I was only put back into payment with a small amount. I wouldn't now be left with nothing and waiting a month or more for UC.
They did not mention if I would have been put back into payment and what amount I would have been awarded even though I can no longer claim ESA but she did say I would be backdated from this on my UC claim and the period in question i wouldnt need my disability to be reassessed. I have put this information on my journal which she asked me to do. Have a feeling they ignore the journal. I just feel like the whole thing is confusing and I have done everything they asked of me and am still being messed around. I don't really understand universal credit and have been reading your guides to help me. Which are very helpful
Before the inheritance I was in receipt of SDP which I will lose now but my main concern is that for those months I won't receive anything and they will just turn round and say UC is separate to the benefits you were on and we will only pay you from when you made the UC claim. I did ask if I would get a letter about all this from ESA and she said I should but I'm going to check on Monday as i want proof of what i was told on the phone as she didnt say i could appeal the decision or anything just i should claim UC asap and write what she said on the journal. ITs so hard to explain so i would want the letter to show CAB legal advice the local authority or potentially UC to help me explain the situation. I still have a PIP claim until 2024 for high rate care and mobility and need to use a wheelchair sometimes due to sezuires even just to get to the UC identification appointment will be a struggle as my carers only come in the morning and in the evening and I can't really go out unsupervised and the appointment is not my nearest Jobcentre to my home by a long shot. I have told them this on the journal and phoned the UC helpline and was told to ask on the journal if I can do it on the phone or via emails. If they refused I will have to try and get there some how. Due to my disability I am regularly at the GP's I was so stressed today I broke down and was honest that I'm not coping and GP has offered to give me a fit note from today just in case I need one for UC so I don't know if I should give them that or wait it out as I don't want to have to provide sick note all the time to UC when I'm long term disabled.

Thanks so much Gordon.
I was never under the impression my claim was closed and kept on sending receipts and statements every month after I received the money and when I moved they didn't say anything about UC just to send them the income form and evidence when I dip below the threshold. I've done everything they told me to do in good faith I wish I didn't bother now tracking every penny getting in a wreck about buying a small fridge not buying anything apart form essentials paying rent and only buying the cheapest flooring for my rented HA flat that had no floor or interior doors. My last flat was condemned by enviomental health due to rats and leaks and landlord not being registered or doing anything but take my money. I didnt have anything and had to start again telling my family I didn't want to travel for my own dads and grandads funerals as I didn't want DWP to see it as a jolly to Jamaica or I'm suddenly cured of the epilepsy I fight with and I didn't go and regret not saying goodbye now. What's the point of being truthful doing everything they asked of me and now I'm screwed anyway and penalised by the one month backdate rule.
Gordon is there anything I can do about that like appeal? Also is there anything I need to do with UC in the meantime do I have to apply or ask for a new disability assessment with UC ?
I have a appointment for my identity proof booked and wrote on the journal what the lady on
the phone told me to do and went to my GP because of all the stress and a check up GP could see i was breaking and gave me a sick note just incase. Thanks again for your help I really appreciate it. I will read some more guides in the meantime I wish I knew about the site years ago. It would have helped me.