I need to know what to do about this or what i can do?

ok im a little confused about this. about a month ago i walked out on my job because i was tired of being hared by my supervisor. i have 3 occurrences against him for just harment and 1 for ual harment. so i leave work and i try calling Human resources to explain why and about 2 weeks later i finally got in touch with them and i told them my complaints against the supervisor and the said the will be doing a full investigation on it well about a week later i call back up there because i have not heard anything in a while. so they say a couple more days. well i get a call the other day and the told me that they couldn't find any supporting evidence about my allegations. so i call one of the witnesses i told them about and asked him if they even talked to him and he said no. so i call back up there and they said they talked to everyone i told them about and then i said no you didn't i talked to the guy and he said you didn't and then she paused for a moment and said i wish you luck in the future but you abandoned us. so that's it and i really need help to see what i should do or what i can do??