Cannot modify the Render Distance setting - Stays at "Far" regardless of changes.

My computer barely runs with far distance and is better off running with normal render distance. However, whenever I attempt to alter the render distance under video settings, the background with blink for a split second and show "normal." After exiting all the menus, it still lags. Therefore, I go re-inspect the settings and find that "Far" is selected under render distance again. Then I select "normal" and keep clicking, where I found out that it's not switching from normal. This happens on both Mac and Windows Operating Systems.