CFT Template error: unresolved condition dependency UseDBSnapshot in Fn::If

Trying to create a CFT for RDS which can handle both the scenarios creating a new RDS Aurora MySQL cluster and create a RDS cluster with a existing DB Cluster Snapshot

Here is what I tried,

I have provide the below conditions section of the template

"UseDbSnapshot" : {
              "Fn::Not" : [
                  {
                      "Fn::Equals":[
                            {"Ref": "DBSnapshotName"},
                            ""
                        ]
                    }
                ]
            }

and referenced in Resource section as below

"RDSCluster1": {
        "Type": "AWS::RDS::DBCluster",
        "Condition": "isResourceCreate",
        "Properties": {
            "Engine": "aurora",
            "DBSubnetGroupName": {
                "Ref": "DBSubnetGroup"
            },
            "DBClusterParameterGroupName": {
                "Ref": "RDSDBClusterParameterGroup"
            },
            "DBSnapshotIdentifier" : {
                "Fn::If" : [
                  "UseDBSnapshot",
                  {"Ref" : "DBSnapshotName"},
                  {"Ref" : "AWS::NoValue"}
                ]
              },
            "MasterUsername": {
                "Ref": "DbUser"
            },
            "MasterUserPassword": {
                "Ref": "MasterUserPassword"
            },
            "StorageEncrypted" : true,
            "KmsKeyId" : {
                "Ref": "KmsKeyId"
            },
            "VpcSecurityGroupIds": [
                {
                    "Fn::GetAtt": [
                        "DBAccessSecurityGroup",
                        "GroupId"
                    ]
                }
            ],
            "Port": "3306",
            "BackupRetentionPeriod": "1"
        },
        "DeletionPolicy": "Snapshot"
    }

The condition "isResourceCreate" is satisfied but I am getting below error

Template error: unresolved condition dependency UseDBSnapshot in Fn::If

Could you please help me here.

Have looked up online link https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/conditions-sample-templates.html and created this CFT.

Let me know if you require any more details.