Being made an apointee

Just been made appointee for son with very complex mental health issues after trying to sort his DWP Paperwork out found all the 19 loans been given
Well now I have all his paper work about all the 19 crisis and one Budgeting loan he has taken out over a long time and sorting out payments for them all. Now they are taken too much money weekly and now I have found alot of post (unopened I might add ) I asking him to agree and post back the slip saying he will pay back what and when, well he has not as i still have them here so I asked him have you agree to payment plan for them he said yeah they made me do it on the phone, they KEPT phoning me .
Now I am his appointee I am trying to sort it all out, was wondering if I right in thinking that because he has not signed an agreement its been done wrong
Well this morning I phone the right department and was told to send a letter to them asking for the payments to be reduced, this i am doing but i was wondering with the fact that my son has 4 possibly 5 different people in his head can this be legal at all not trying to get out of the payments just angry its got to this point not everyone has someone looking about for them it just makes me slightly mad to thing this is caring on. has anybody else been having this sort of trouble them asking for to much money back on payments
Thank you for reading in advance

Thanks very much for the reply sorry to of posted this then that's why i could not find anything to do with appointee`s sorry Gorden