Remove esxi Host from cluster

HI gurus

as you can tell still learning vmware, so need some help

I would like to remove a host from the cluster , so I have read and found the followng steps

1) remove hosts from vDS

2) add to new cluster

The problem that I am finding is that when I go to the vDS to remove host from vmotion/fault Tol. I get the same error  " vDS  dvswitch  port # is still on host "

how d I go removing esxi host from this cluster.

Thanks a bunch