Data Integration - target cube 'missing' in DLR

Summary:

Content (please ensure you mask any confidential information):

When I try to create a new DLR in data exchange or modify an existing DLR, I've noticed that the target cube is missing within the target application section:

Example below is an existing DLR - notice the cube field is blank within the target application:

When I make some other modifications e.g. within options or clear region and click save, or even if I just click save without modifying I get the following error telling me that the mandatory field is missing

When clicking show log, nothing happens

It looks like the target ASO cube is just missing from the target application.