I tried multiple times with different accounts but still getting following error on step #3

Challenge Not yet complete... here's what's wrong:
We can't validate the 'Create Seed Bank Agencies' node was created correctly. Check the required fields, field types, node name, and alias are correct.
JSON: 
{
  "Filter Agency Records": {
    "action": "filter",
    "parameters": {
      "filter": "IsAgency:EQ:TRUE",
      "source": "ID Agency Records"
    }
  },
  "Load Account": {
    "action": "sfdcDigest",
    "parameters": {
      "fields": [
        {
          "name": "Name"
        },
        {
          "name": "AccountNumber"
        },
        {
          "name": "Phone"
        },
        {
          "name": "ShippingCity"
        },
        {
          "name": "ShippingCountry"
        },
        {
          "name": "ShippingPostalCode"
        },
        {
          "name": "ShippingState"
        },
        {
          "name": "ShippingStreet"
        }
      ],
      "object": "Account"
    }
  },
  "Create Seed Bank Agencies": {
    "action": "sfdcRegister",
    "parameters": {
      "name": "Seed Bank Agencies",
      "alias": "seed_bank_agencies",
      "source": "Filter Agency Records"
    }
  },
  "Add Agency Fields": {
    "action": "augment",
    "parameters": {
      "right_key": [
        "AccountNumber"
      ],
      "left": "Load Account",
      "left_key": [
        "AccountNumber"
      ],
      "right_select": [
        "Acres",
        "Currency",
        "Latitude",
        "Longitude",
        "Region",
        "SubRegion"
      ],
      "right": "Load Agency Detail",
      "relationship": "AgencyDetail",
      "operation": "LookupSingleValue"
    }
  },
  "Load Agency Detail": {
    "action": "edgemart",
    "parameters": {
      "alias": "Agency_Detail"
    }
  },
  "ID Agency Records": {
    "action": "computeExpression",
    "parameters": {
      "source": "Add Agency Fields",
      "mergeWithSource": true,
      "computedFields": [
        {
          "name": "IsAgency",
          "saqlExpression": "case when Phone is not null then \"TRUE\" else \"FALSE\" end",
          "label": "IsAgency",
          "type": "Text"
        }
      ]
    }
  }
}

Thanks,
Suramya