Invalid value for field resource.tags.items

When trying to provision a new CVO cluster with custom firewall rules, getting error:

Error: Failed to create CVO, error: Operation Deploy failed with error Error: Code: RESOURCE_ERROR

Target: /deployments/nacvogcptest1-deployment/resources/nacvogcptest1-mediator Message:

{"ResourceType":"compute.v1.instance","ResourceErrorCode":"400","ResourceErrorMessage":{"code":400,"errors":[{"domain":"global","mes

sage":"Invalid value for field 'resource.tags.items[0]': ''. Must be a match of regex

'(?:[a-z](?:[-a-z0-9]{0,61}[a-z0-9])?)'","reason":"invalid"}],"message":"Invalid value for field 'resource.tags.items[0]': ''. Must

be a match of regex '(?:[a-z](?:[-a-z0-9]{0,61}[a-z0-9])?)'","statusMessage":"Bad

Request","requestPath":"https://compute.googleapis.com/compu...est3-c/instanc

es"," httpMethod":"POST"}}