What is one valid reason for refusing a service request?

Refusing a service request due to a modification made to the device is a valid reason because modifications can impact the device's performance and might lead to complications that are not covered by standard service policies. When a device has been altered, it often voids warranties or service agreements, as manufacturers typically provide service based on the device's original specifications. This means that any issues arising from the modification fall outside the scope of the manufacturer's support. Therefore, if a device has been modified, service centers may be justified in refusing the request to avoid liability and to comply with warranty guidelines.