Many ads keep reaching the same people because the audience you selected might be too small. When the platform does not have enough new people to show the ad to, it repeats the same viewers to use up your budget. Another reason is that your settings may be focused on people who already interacted with your page, so the system keeps choosing them since it believes they are more likely to respond. You can test a bigger audience or remove limits that are too narrow. A small change in age group, interests or location can help the ad reach fresh eyes. What do you think?