As of April 12th, you must go to Progress SupportLink to create new support cases or to access existing cases. Please, bookmark the SupportLink URL and use the new portal to contact the support team.
This was fixed over a year ago. Drag and drop a new certificate, then hit the save button.
Have you ever fixed this without changing the environment?? its very cheap that this problem have been existing since a year ago, doesn't seem like Kinvey is doing anything about it.