Media upload issues

Every time I try to upload an image, it a) doesn’t upload and b) creates hundreds of broken thumbnails.
I de-activated all plugins and after re)activating one by one, Jetpack is the one causing the issue.
I checked the folder permissions and it’s not that.

I saw similar issues on this support thread. The steps described in the link that was provided in similar threads are 8 years old and also require developer knowledge which I do not have.

I also noted on a wordpress.com forum that there had been issues with the media upload acknolwedged by Jetpack (https://en.forums.wordpress.com/topic/media-uploading-issues/page/3?replies=89).

Would you be able to let me know what to do to fix my issue?

Thanks

https://ww.wp.xz.cn/plugins/jetpack/