Error: Service Unavailable. upstream connect error or disconnect/reset before headers

Question

I have build a docker image in aws ecr and deployed it through aws app runner. It contains background jobs. It contains two tasks, first one take less time to execute, second one takes more time. When i call the first one i am getting output. But when i am calling second task i am getting 503 Error upstream connect error or disconnect/reset before headers. I have set time limit to 60 using uvicorn before buiding docker image and pushing it to ecr. It worked fine with ec2 instance. Can some one tell me where is the problem. If timeout is the issue how can i increase the timeout