{
  "$schema": "https://schema.management.azure.com/schemas/2015-01-01/deploymentParameters.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "vm": {
      "value": "vmName"
    },
    "domainJoinUserName":{
      "value": "contoso\\username"
    },
    "domainJoinUserPassword": {
      "value": "GEN-PASSWORD"
    },
    "domainFQDN": {
      "value": "contoso.com"
    }
  }
}

{
  "$schema": "https://schema.management.azure.com/schemas/2015-01-01/deploymentParameters.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "vmName": {
      "value": "vmName"
    },
    "domainJoinUserName":{
      "value": "contoso\\username"
    },
    "domainJoinUserPassword": {
      "value": "GEN-PASSWORD"
    },
    "domainFQDN": {
      "value": "contoso.com"
    }
  }
}

Change parameter VM for vmName on parameter file.
Change parameter VM for vmName on parameter file.
