creating an IPI Azure cluster, then modifying the MachineSet to set the resourceGroup to a capitalised version, then scaling up some Machines in that MachineSet， machines could join the cluster.
$ oc edit machineset zhsun616azure1-r62jc-worker-eastus23
$ oc get node
NAME STATUS ROLES AGE VERSION
zhsun616azure1-r62jc-master-0 Ready master 164m v1.17.1+912792b
zhsun616azure1-r62jc-master-1 Ready master 164m v1.17.1+912792b
zhsun616azure1-r62jc-master-2 Ready master 164m v1.17.1+912792b
zhsun616azure1-r62jc-worker-eastus21-whk9x Ready worker 151m v1.17.1+912792b
zhsun616azure1-r62jc-worker-eastus22-vl9jb Ready worker 150m v1.17.1+912792b
zhsun616azure1-r62jc-worker-eastus23-86gpn Ready worker 151m v1.17.1+912792b
zhsun616azure1-r62jc-worker-eastus23-szn9j Ready worker 119s v1.17.1+912792b
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.
For information on the advisory, and where to find the updated
files, follow the link below.
If the solution does not work for you, open a new bug report.