UC and wrong info given

My son turned 19 yrs so I assumed he should come off our UC claim and make his own in which he did. However, we then found out as he had been removed we lost a bedroom entitlement which meant we lost money on housing element. UC told me to put him back on our claim and for him to close his claim. I didn’t think this was right I kept asking on my journal was it correct as I didn’t want an overpayment. However we then were contacted by UC and told to put him down as a none dependent which I did.

He was told to claim for himself.

All of this messing around resulted in a £500+ overpayment for us and my son lost out on two months of UC. He has now put in another claim.

My question is should they not back date his claim as they are taking the overpayment off us but he missed out and it was due to their error and wrong information and instructions by the UC. I have all of the information on my journal whereby I’m asking constantly is this correct as I didn’t believe it was and was concerned about ending up with an overpayment and was told it was correct.

I have also been classed as sick for a number of years. I was on ESA then when I got married we had to make a joint claim for UC. As I was receiving carers allowance for my son this was taken into account. I have recently advised them that I am no longer in receipt of Carer’s so they have put me on LCW. Should I not be placed on the next level of LCW because I have been poorly for a number of years? And highly unlikely that this will change as I’m getting worse. If not how do you get put on the next level (sorry I can’t remember what it’s called)