esa support group to universal credit nightmare

hi,im at a loss,my son was on esa support group but moved to universal credit,he was due a home visit medical but had not recieved a date ,now he has moved universal credit are paying him basic mony 74 per week and are not paying esa amount as they are saying they have not heard from esa to say hes in support,however e s a say he is in support and should be kept in it until at least his medical.i have spoken to e s a o 3 different occasions,and they say they have notified u c.universal credit woman on his journal keeps saying she hasnt got information so cant add it,this has been going on for 3 months,its like bashing your head against a wall.i have just made an online complaint,hopefully that helps ,anyone else had this problem