It often happens that a high setting for wrapping of a photo squashes or entirely pushes out caption placed in a text box underneath.
Reducing the wrapping count of the photo will bring text back inside the box. But you may want to keep it high for design purposes, for example to set the main body of an article flow farther away from the picture.
One easy way to solve the problem is to
bring the Text Box to front
Select the text box and bring it to front under Arrange menu. Or use the keyboard shortcut: