MQL5 Cloud Network status change from "ready" to "not used"

I tried to start optimizations on the Cloud Network and before I start, the Cloud Network is enabled and I can see the status as "ready" for both my local agents and the cloud agents. There is also sufficient balance for an optimization to start. The Journal also confirms "cloud servers switched on". However, when I try to start the optimization, the local agents become "busy" and the cloud agents immediately switch to "not used" status. I have searched through all of MQL5's documentation and have not been able to find a solution or reason why this happens. There is no error message given in the Journal either. Any idea why this is happening?