Is paying installments for gas delivery to the company, with the phrase "loan installment" in the contract, considered an interest-based loan or an installment sale with a commission?

If the company involved the bank in the transaction as a lender with interest, then this is a usurious loan forbidden [in Islam]. Clients must rid themselves of it by expediting the repayment of the loan without interest, or by rescinding the contract if no significant harm results. However, if the bank's role is merely administrative and organizational (which is unlikely), then there is no objection to it charging a fee for its work.