Structure Block unable load

Steps to Reproduce:

1. In World (A), place Structure Block around the preferred structure 
2. Set the size (XYZ - mine was 32x32x32) - ensure within the bounding box and set mode to 'load' 
3. Click on 'Export'
4. Type the name of file and the format has been set automatically (as mcstructure)
5. In World (B), set the mode to 'load'
6. Click on 'Import' and will be directed to dialog box.
7. Choose a wanted file structure. 
8. Click Load.
9. A structure ''WILL BE'' built.

Observed Results:
I have tried to load a structure from one world to another world. however, the saved/ imported structure didnt show up. Then, the structure block disappeared.
Retried it again and again. however, it was no success.

Expected Results:
There should be an exported structure showing up in my other world.