Cannot access new account after moving

I had to temporarily move from my actual apartment to a temporary apartment next door. For this move, I changed my service address and everything went very smoothly. After repairs were complete on my actual apartment, I changed my service address back to the original address and it was not smooth at all. I am still unable to log into the new account that was created for this move. I have called and nobody seems to be able to understand what is happening, they seem flabbergasted. I am not sure what is unique about my situation at all. I would be extremely grateful if someone could help me regain access to my account.