Thanks @Mithun_Shetty ,
Using connectors: Using connectors come in handy if you want to easily make rest calls and use the modeler to do so. However, if a connector call fails (ie restendpoint down or failure to set a variable by the rest endpoint) such error won’t be caught by Camunda. So you need to make sure to check the response from the rest endpoint. If there is an error you can retry or set the retries to zero to throw a technical error which you can later see in cockpit. You could also throw a BPMN error eventhough this is meant for business errors like this [REST-API] Service Task Error Handling.
Your process: I managed to succesfully deploy a similar setup as per your process and rest endpoints and I was able to execute everything correctly. I did not get any errors. I am starting to think that there might be something wrong with your environment. Can you share your POM? Also, I see that you are trying to set and get variables with your rest endpoints. Have you considered doing this by using Java Delegates with Camunda like this https://docs.camunda.org/get-started/java-process-app/service-task/?
Also, sorry that you are in a rush to do a demo. What type of demo are you trying to do? Are you trying to showcase Camunda?
Regards,