Errors for importing the implanted CT

when importing the implanted CT, right-click on Subject and choose Import MRI. After selecting the CT image, an error occurs:

Error: Line 1968: Index in position 1 is invalid. Array indices must be positive integers or logical values.

Call stack:
> panel_surface.m > UpdateSurfaceData at 1968
> panel_surface.m > SetSurfaceData at 1626
> panel_surface.m at 40
> view_mri.m at 230
> import_mri.m at 467
> bst_call.m at 28
> tree_callbacks.m > @(h,ev)bst_call(@import_mri,iSubject,[],[],1) at 575

Could you please help me understand what might be causing this issue?

From the error stack, it seems you clicked on Import MRI rather than Import CT