Process stuck

It looks like you're trying to call a Web Service - have you been able to connect to the same Web Service using a different node/process?

It also looks like you have MNI set up on that node. I would check the logs. Is the connection being refused, connection timed out, or MNI issue (setup, load, etc).
I would check there first.

If you have that node configured with an expression for MNI or one for item in a list, and the list is empty or the rule returns 0, it will just stop like this. check to make sure the logic guiding the MNI returns a number greater than 0.

Check the value that is entered for MNI. As Davidg707 said, the value is either blank or 0.

The reason here is the max number of instances allowed to be run in a process is 1000 and the array has more than 1000 values. Custom.properties - server.conf.processcommon.MAX_NODE_INSTANCES=1000

Solution - Use batch processing or increase the value. I would suggest first approach.

In Addition to the above comments given by Sagar, Cant we enable the Checkbox of Delete previously completed/cancelled Instances. Also When it comes to calling the Service with MNI, We see that some of the instances are getting failed as the Web Service server should be able to accept the multiple concurrent requests and respond within time out. Its better to Use batch processing so that we hit the server with a limited number of requests and get response within the timeout

I did not notices there was MNI at Call Web service node. But I reckon the better option for me to replace the MNI logic .