Indonesian-Language Application-Based Guided Imagery Therapy for Insomnia and Glycemic Control in Diabetic Patients

The goal of this clinical trial is to learn if guided imagery therapy using mobile application in Indonesian language can improve sleep quality and lower fasting blood glucose levels in diabetics patients who have problems with their sleep. The main questions it aims to answer are: * Can the app-based guided imagery therapy help improve sleep quality in diabetic patients who have trouble sleeping? * Can the app-based guided imagery therapy help lowering fasting blood glucose in diabetic patients who have trouble sleeping? Researchers will compare app-based guided imagery therapy to education about how to sleep well, to see if the app works to improve sleep quality and lower blood glucose. Participants will: * Receive education about how to sleep well * Use the app 3 times a week for 4 weeks (only for group who receive the app) * Visit the clinic after 4 weeks for tests