Adobe Community Professional, Feb 04, 2021Feb 04, 2021
Barb Binder • Adobe Community Professional, Feb 04, 2021Feb 04, 2021
If you cannot select an object it's because:
The object is locked. (Object > Unlock all on Spread)The layer the object is on is locked. (click the padlock icon in the Layers panel)The item is on a master page and you are on a body page. (Double click the master page name at the top of the Pages panel.)It is fully covered by another object. (Hold Ctrl/Cmd and click until the selection handles activate.)
You said this is in the footer, so I would suspect that the flag is on the master page.