Billing Issue

I have a serious problem. I’ve been a loyal customer for 30 years. My phone was cut off to find out my bill was 1800 plus dollars , I had to pay 800 before anyone would talk to me I paid the $800 and was able to talk to someone to find out that somehow my service was switched to megabytes and not unlimited. I’ve always had unlimited. They promised they will give me my $800 back and they would take the charge off. It’s been three months and I still have the same problem. I just paid $112 for my phone service and then after that my big bill for $1200 pops up I am looking for a refund which was promised of my $800. They told me to look in the mail for my $800 never received it. It’s been three months and I’m still having the same problem. They’re getting ready to cut my service off again. I lost one of my phones, but I cannot get anything done until they say I pay the 1200 I call some people and they say that I owe 1200 then I called back and and people say that they will refund my money. Somehow my account was twisted up. I’ve been a loyal faithful customer I please I need someone to get this straight now I need my money refunded back to me. I need that $1200 taken off of my account and I need it done soon please please please help me out. I can’t even talk to them about my phone that’s lost because they asked for $1200. The phone has been lost for a long time but I can’t talk to anyone because they say I have to pay the $1200. I need some help. I don’t know what else to do. [Edited: “Personal Information”]