The goal of this clinical trial is to determine whether there is an increase in participant uptake of diabetes mellitus (DM) and diabetic retinopathy (DR) services and improved quality of patient-centered diabetic care resulting from the use of automated voice message reminders to sensitize people with DM about the potential for sight loss alongside the provision of free reading glasses. The main questions it aims to answer are: 1. Will the proportion of patients completing their scheduled DR and DM appointments within 3 weeks of the scheduled date be significantly increased in the group receiving the automated voice messages containing both appointment reminders and messaging about the importance of visit and medication compliance in reducing the risk of vision loss, compared with participant messages which only remind them of their appointments? 2. What is the cost-effectiveness, measured as total intervention cost per additional patient complying with the suggested exam?