Nifi Ui still says flow controller is still initializing

[Premfer]

Hi,

I deployed nifikop using nifi , all are deployed correctly but UI says flow controller is still initializing. The log of nifiKop says

2021-08-11T13:34:38.775Z INFO scale-methods Retrieving Nifi client for nifikop/simplenifi

Wed, Aug 11 2021 7:04:38 pm | 2021-08-11T13:34:38.780Z INFO nifi_client 404 response from nifi node: 404 Not Found Wed, Aug 11 2021 7:04:38 pm | 2021-08-11T13:34:38.780Z INFO controllers.NifiCluster Nodes unreachable, may still be starting up

Can you let know what is the thing need to be checked ?

[Premfer]

I am running this in Rancher and storage class used is longhorn. All pods are running but still getting this issue.