Access facility at bank

I have a loan at a bank (non-islamic) at a fixed rate. I also have an access facility (account) at the same bank that allows me the following:
I am able to make use of the cash in my facility
. Cash in my facility is used to reduce my interest rate on my loan or
Monthly repayment including interest is calculated as (outstanding balance – facility + interest / re-payment period)

Is this jaaiz?