aws-amplify subscription to appsync stops after 2 mins

Question

When subscribing to appsync using amplify using API.graphql(graphqlOperation(subscription)); the subscription works for a while, but the I get socket closed error.

CONSOLE LOG [native code]: {
"[INFO] 24:12.893 MqttOverWSProvider": {
"errorCode": 8,
"errorMessage": "AMQJS0008I Socket closed.",
"uri": "wss://<uri>

The same subscription works in the appsync console without any issue and I get events as long as the subscription is running, but stops after around 2 mins on device.

code involved

let cs = await this.subscriptionService.appSubscriptions();
    this.sbscriptions = this.cs.subscribe({
      next: data => {
        console.dir(data);
              },
      error: error => console.dir(JSON.stringify(error)),
      close: () => console.log("closed")
 });

This part of code throws no error, and the error shown above is only visible when setting LOG_LEVEL = DEBUG

NOTE : The subscription does work for a while before this error shows up, and in that time I can see all the events that I trigger from console.