You have placed a Schedule or Index as Drawing on a Layout.
The length of such items can change dynamically as the project progresses so they may or may not fit on a single Layout when placed as a Drawing. Thus the Multi-Layout option is available for Drawings the source of which is a Schedule Viewpoint or Index Viewpoint.
Select the placed Drawing, go to its settings Dialog, and in the Frame panel, under the Fit Frame to Drawing radio button you will see that the Split Drawing among Multiple Layouts checkbox is checked. Thus the multi-layout graphic is displayed.
You can uncheck it and the multi-layout graphic display will disappear.
The checkbox is enabled only if the source of the selected Drawing is a Schedule View or an Index View.
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