Is the subscriber's failure to pay accumulated internet service bills considered a sin, given that the company breached its initial promises regarding service stability and significantly reduced the internet package, and the subscriber was unable to fully utilize the agreed-upon package?

The resolution of disputes takes place in the judiciary because it hears from the parties to the dispute and issues a judgment based on that, whereas a mufti (issuer of religious opinions) only hears from one party. The sale of services falls under leasing contracts ('Uqud al-Ijarah), and a leasing contract is not valid unless the benefit is known in terms of its essence, quantity, and description. If the lease is invalidated due to ambiguity of the benefit, and the benefit has been utilized, then the ajrat al-mithl (customary rent/wage) determined by experts becomes obligatory. The lessor is not permitted to change the extent of the benefit without the lessee's acceptance. Therefore, it is not permissible for a contract to contain a clause granting the company the right to modify the service whenever it wishes without consulting the client, as this leads to ambiguity of the benefit and potential disputes.