Using Collegeboard college fee waivers; UC vs CSU

hi I am a parent to a prospect student and when submitting sons UC application, it said denied fee waivers when we already used the waivers for scu colleges. And originally said he had 4 UC waivers. I can not find a way to change anything nor is it giving me the reasons why denied!!! SOS HELP ASAP thank you Yasmina graves