When an SME interface is deleted on one switch in a cluster and then added back, even if the saved SME configurations were the same, the SME interface will not be added back to the cluster.
When the switch is reloaded, the SME interfaces will not be added back to the cluster due to a certificate mismatch (because the SME interface was removed and then added back). You need to delete the SME interface and add it back, and then enter the copy running-config startup-config CLI command.
Note You must enter the copy running-config startup-config CLI command after adding or deleting interfaces or switches.