I'm having this issue (minus the error message) as well. Currently (trying) to upload a 1.47GB package and its hanging at 99%.
Can anyone report on whether this is an ongoing issue?

Thanks!

I'm also having this issue minus the error message. I've tried uploading through Safari, Chrome on my Mac and Jamf Admin. I've also tried uploading using a W10 using Chrome all attempts fail. Jamf Admin gives an error 504. My users are also having issues installing currently uploaded packages from Self Service as well which may be a coincidence. This is all on Cloud.

Seems like this is still an issue. Looking at migrating to Jamf Cloud but still seeing this issue in a trial instance.

I am having a different error today, but I am also unable to upload to the cloud DP. I tried de-selecting the cloud DP and now I am unable to select it again.

I am having this same issue. Unable to upload a 22 MB file. It stops at 100% and never successfully completes the upload. A test of the connection to the Jamf Cloud Distribution point returned an Error (!), but no messaging. Now I simply get the message "Unable to communicate with JAMF Cloud". Has anyone found a resolution for this?