I have run some tests on the MIT CloudDB and on my own online redis Server
In both companion mode and with compiled apps, my test project worked OK, without any errors. Therefore there does not appear to be an issue with the MIT provided CloudDB nor with a correctly configured self provided redis server.
You will need to look at your configuration and your blocks to identify where the issue lies. It could be a network issue, in which case you may need to run a network check in your app before connecting to cloudDB.