Product: Debt collection

I really need your help to solve this. I am super close to getting my number changed just to stop the phone calls and text messages even though i blocked their number they call from a different line? I had purchased a bed at XXXX XXXX XXXX in XXXX or XXXX XXXX. I have paid this loan off before i moved out of state. I as well made sure the bank account was closed after i fully checked with that balance was paid off. I get phone calls multiple times a day as well as emails. I have opened two fraud complaints with the company ; they state that i will not get calls about the past due " balance '' but they never go through with the complaint. I have tried to get loan officers to help as well. None of this or the dozens upon dozens of times i have communicated that this is not my debt. my monthly minimum payments were {$5.00} but i always paid {$100.00}. my total was just around {$2000.00} but not exceeding {$2200.00}. I know i paid this off and i am getting harassed so many times a day i had to block their number. This is the most recent email that i have received : Payment Due Date : XXXX Statement Balance : {$2300.00} Total Minimum Payment Due : {$650.00} Payment Due Date : XXXX Statement Balance : {$2200.00} Total Minimum Payment Due : {$530.00} Payment Due Date : XXXX Statement Balance : {$2100.00} Total Minimum Payment Due : {$400.00} Payment Due Date : XXXX Statement Balance : {$2000.00} Total Minimum Payment Due : {$290.00} Payment Due Date : XXXX Statement Balance : {$2000.00} Total Minimum Payment Due : {$170.00} Payment Due Date : XXXX Statement Balance : {$1900.00} Total Minimum Payment Due : {$67.00} my " monthly bill '' has gone up {$600.00}. 
I couldn't find the other emails that go back farther. I also sent my ( when i actually bought my bed ) payments over check. 

The balance is going up and up and i did not purchase anything besides 1 transaction in XXXX. I have been getting harassed by this company for almost two years now. 

Even though this is not my debt i closed that bank account associated with that loan after i paid it, and i waited for it to completely cleared when i moved to XXXX  on XXXX however, some of the emails from this company states that my last payment was in XX/XX/XXXX. It is not feasible that i could have made payments let alone owe around {$2400.00}. This has a hold on my credit and my XXXX XXXX has gone down due to this company. I would like to solve this and get my XXXX XXXX back up. I do not have a single debt collection in my name for i pay all my bills! I cant have up to XXXX phone calls a day not listening to me and telling me that i have to pay this regardless if its not mine. 
I do not know my account number associated with this fraudulent affair due to the fact i paid my full balance and i can not get in to see someone used my account to purchase {$2400.00} loan. the only action that i have not taken was to send a cease and desist letter. I do not have access to any statements or itemized list from the company since i do not know what my account number is and when asked they told me they couldn't tell me that. I hacve not given my updated address for i didn't want to be harassed by letters as well.