ID:150048 Cannot locate top-level file in hierarchy

CAUSE: You chose Hierarchy < Project Top; however, the Quartus Prime software cannot locate the file. This message can occur if the design was not compiled, and the file and related entities are not stored in the project database, so the Quartus Prime software cannot locate the file or entity.

ACTION: Click OK to close the message dialog box, and then analyze or compile the design containing the selected entity.