we are using java Agent Auto Instrumentation for jars for signoz and there is Eureka Client is registered for every springboot microservice, when i attach java agent to the jar actuator API /acuator/process.uptime is returning Nan as value due to which microservices are getting restarted every few minutes.

This is coming from the instrumentation. You might have to figure out why this happens. May be search here https://github.com/open-telemetry/opentelemetry-java-instrumentation