Why wasn't the ETC fee deducted after exiting the highway?

[DeCharlie]

There are two scenarios where highway ETC fees may not be deducted immediately: First, when the barrier arm is damaged and the vehicle passes through the ETC lane too quickly, causing fee deduction failure. Second, when the ETC system operates on a postpaid accounting basis, meaning fees won't be charged instantly but will be deducted within a specific billing cycle. ETC usage precautions: The ETC transaction sensing range is 8 meters. When encountering a stationary vehicle ahead, maintain a distance of over 10 meters to prevent accidental fee payment for the preceding vehicle, which might occur if their ETC device malfunctions or is absent. The ETC lane recognition speed limit is 20km/h. Exceeding this speed may prevent successful reading of vehicle device information, leading to fee deduction failure. Unauthorized removal or displacement of OBU equipment, or detachment/loosening of ETC electronic tags will deactivate the device. These issues can be addressed at the bank where the ETC card was issued or at highway service centers. For non-intentional loosening or detachment, simple reactivation suffices. When using debit cards linked to ETC, insufficient balance may cause fee deduction failure. Follow staff guidance to proceed through manual MTC lanes using cash or card payments. Excessively thick windshields may cause poor signal reception. This particularly applies to vehicles with replaced windshields after accidents or those with modified front windshields.