question

I am trying to create VBA code in excel send an SMS text to a short list of customers.

I have the following code and I can use a GET function and received responses from the API but when I try to POST an SMS I get an Error 400 Bad Request.  Not sure if my formatting is wrong or what?  I would also appreciate input on better VBA code to obtain authorization.  I am currently copying the active authorization code from my Sandbox which is only temporary.

Ultimately I want to execute this in a loop and post the send/read status to a cell in my spreadsheet by the number texted

Thanks in advance for any help.

Sub cmdOAuth2_Click()


  Dim webServiceURL As String
  Dim actionType As String
  Dim targetWord As String
  Dim actionType2 As String
  Dim targetWord2 As String
  Dim sMsg As String
  Dim sToPhone As String
  Dim sFromPHone As String
  
  
  webServiceURL = " https://platform.devtest.ringcentral.com/restapi/v1.0/account/~/extension/~/sms";
  actionType = "Accept"
  targetWord = "application/json"
  actionType2 = "Authorization"
  targetWord2 = "Bearer Code copied from sandbox (Is there a better way to obtain auth within the VBA code"
  sMsg = "test from excel"
  sToPhone = "+17313632593"
  sFromPHone = "+12055178260"
  
' use late binding
  With CreateObject("Microsoft.XMLHTTP")
    .Open "POST", webServiceURL, False
    .SetRequestHeader actionType, targetWord
    .SetRequestHeader actionType2, targetWord2
.Send _
"{" & _
        """from"": [{""phoneNumber"": ""+12055178260""}]," & _
        """to"": {""phoneNumber"": """ & sToPhone & """}," & _
        """text"": """ & sMsg & """" & _
        "}"
        
    If .Status = 200 Then
      Debug.Print .responseText
      MsgBox .GetAllResponseHeaders
    Else
      MsgBox .Status & ": " & .StatusText
    End If
  End With


End Sub