Warning! This service has been deregistered and no longer exists in the catalog

i have an issue with service registered on consul .
I am creating 2 instances of same job and they are scheduling on two different client nodes . Because i want to run them in High Availability.
i have added a single service in nomad job configuration file. The job is deployed successfully and service i also created .
But the service is conficting, it is getting registered and deregistered frequently, sometimes point to client node 1 and sometimes to client node 2.
I don’t understand why this happening .
[Note : If i stop the one node and then run the job , then it works fine]

Please suggest me how i can resolve this issue.