Universal credit

I am trying to claim UC for my 20 yr old Grandson who has Autism , I am his appointee , he was supposed to have been paid on the 17th of Feb and to date still has'nt been , on top of which the lady dealing with his claim told us he would get 53.00 a week regardless of the fact that he is not fit for work and will never be able to hold down a job , my local Dial Center Disability North have assured me he should be put in a support group and should receive appox 120.00 a week , anyone any wiser ?
I put a comment about non payment on his journal last week and only today have they commented on it that they will look into the matter . It really is so frustrating