In my team, we have an application named FOX, for which a release was made yesterday night. Developers tried to release version 7.9.2.2 in FOX, where they triggered deployment job as usual in the order of DB deployment in non kubernetes environment, and also deployment job for API, Backend, Control and Front-end modules in Kubernetes environment. But FOX prod link was down for about 40 mins with the below error.

The main reason, why the modules were not working properly was, there were some changes in Hazelcast configuration, which is used by API, Backend and Control modules. But Developers forgot to deploy Hazelcast, hence it was picking old configuration and was not working.

Can you help me writing an email to developers to tell about this issue so that they can take care in future. Provide your response in exactly 3 paragraphs (separated nearby paragraphs with 3 aterisk symbols ***).
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