UI does not reflect the rebalance progress when rebalance is started through cli

i added a node and started the rebalance of 1->2 nodes through cli but UI does not reflect the rebalance making progress

cli command : /opt/couchbase/bin/couchbase-cli rebalance -c localhost:8091 -u Administrator -p password --server-add=10.248.137.140:8091

first node has two couchbase buckets and one bucket has 10k items and the other one has 0 items

i confirmed that rebalance is still going on by visiting
http://ec2-67-202-48-44.compute-1.amazonaws.com:8091/pools/default/rebalanceProgress

{"status":"running","ns_1@10.248.137.140":

,"ns_1@10.248.37.216":{"progress":0.4169921875}}

I opened chrome developer tools as well and didn't find any console errors or any other call that is stuck or is timing out