When I import a json file from Adobe After Effects, I am not able to drag it onto the canvas

https://preview.webflow.com/preview/homewood?utm_medium=preview_link&utm_source=designer&utm_content=homewood&preview=31ea800444a283bed34d7811c2402c8b&workflow=preview

I am following this webflow tutorial on how to make a video that advances with scroll:

I was able to get the mp4 into Media Encoder and got an image sequence, I configured it in After Effects and outputted it in Bodymovin. This produced a json file. I uploaded the json file into Webflow. At this point, the tutorial says to drag the json file onto the canvas. Webflow won’t let me do that. I don’t know what I’ve done wrong. Can anyone help please?