Each node is connected via Cisco 3850

Disk Information Not Available
Failed to get disk information on host DE700193900056-01-01.
ESXi host (DE700193900055-01-01)
An error occurred when attempting to connect to host at null.
ESXi host (DE700193900056-01-01)
An error occurred when attempting to connect to host at null.
ESXi host (DE700193900057-01-01)
An error occurred when attempting to connect to host at null.
Management password
An error occurred while validating the provided ESXi password. Consider using a new password, or attempt to re-validate.
Management username
An error occurred while validating the provided ESXi user name. Consider using a new user name, or attempt to re-validate.
Root password
An error occurred while validating the provided ESXi password. Consider using a new password, or attempt to re-validate.
config.validation.host.0.communication.error
Communication Error (DE700193900057-01-01)
config.validation.host.1.communication.error
Communication Error (DE700193900055-01-01)
config.validation.host.2.communication.error
Communication Error (DE700193900056-01-01)
hosts.DE700193900055-01-01.systemInfo.vendor
Failed to find hardware manufacturer model from node MarvinId {id=DE700193900055, totalSupportedNodes=1, position=1}.
hosts.DE700193900056-01-01.systemInfo.vendor
Failed to find hardware manufacturer model from node MarvinId {id=DE700193900056, totalSupportedNodes=1, position=1}.
hosts.DE700193900057-01-01.systemInfo.vendor
Failed to find hardware manufacturer model from node MarvinId {id=DE700193900057, totalSupportedNodes=1, position=1}.
misc
An internal server error occurred during environment preparation for WitnessHostValidator.

How do I fix it?