unable to connect DFS

It been 2 month that i try to connect into DFS and it seem impossible. I'm pretty sure that my refund is already all paid but I can't connect and see how much left i need to paid and the DFS continue to take money from my account. I bought the pc and put a 3 years payment from march 2019 and we are now october 2022 and I continue to paid. I tried alot of time to connect and all the time i got this 2 error from DFS. 

-sorry something went wrong please try again. Error code : 4444

or

- Error code : out of memory or page not found

So now which is my option left to me? Is it to block DFS to take money from my account and tell my financial institut to block DFS that try to take money? Or there another solution to me and finally be able to connect and see how much I need to paid or how much they need to refund me.