When there are two buttons, how do i properly indicate that one is active whitout being ambiguous? [duplicate]

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When you have a list with 3 or more buttons, its essencially easy to show the system status to the user, but for the first time i faced this two-button status feedback, and i don't know how to proceed. enter image description here

How do i indicate that the button previously clicked is active? without confusing the user.

EDIT: To clarify the question, i will explain the use case of these "tabs" as Marné said below. These are buttons that will change the page content when one is active/clicked, but even when one is clicked the other still enabled to be used, it is more like a "switch" interation. But because a lot of content changes, I considered important to show the user which one is currently being used.