Account visibillity lost - No service to resolve

I have been with FNB for years and has always had a fantastic experience! I feel disheartened with the service I am receiving with a problem on my revolving credit account which has disappeared from my profile. I can't access the statements and has no visibility on the account. I have explained this to numerous consultants and I am passed from one consultant to the next. I feel so disappointed. I am a loyal and committed customer with them and I feel very let down with this situation.