Search for subform record based on text box

I am trying to bring up a form record based on text entered in a text box.

The form "Furnace + Header Data Form" is a parent form, with 2 subforms called "Header Data Form" and "Surrogate Data Form". This question is in relation to the "Header Data Form" subform.
The parent form is used to enter data on different furnace runs, which is connected to the table "Furnace Run Data". Each furnace run will have several headers in it, and each header has a serial number. I added a subform called "Header Data Form", which will allow the user to enter information specific to each header serial number. Data that is entered into the "Header Data Form" subform adds data to the "Header Data" table and is connected to the furnace data table via the Furnace Run ID. The Furnace Run ID is on both the parent form and as an invisible field on the Header Data subform. All fields on the Header Data Form are connected to the Header Data Table.

As a side note, there is a button within this subform to add a new record. Once the button is clicked, a new record with the furnace data and header data is saved and the header data subform is cleared. When you enter more data into the header data form and click the add button, another line (with the same Furnace Run ID) will be added to the header data table. No data is added to the furnace table. This all works great. There are multiple records in the Header Data table for each Furnace Run ID.

Initially, I was trying to find the record based on a text field named "Header SN Field" on the subform named "Header Data Form". This text field is connected to the "Header SN" Field from the "Header Data" table. Upon clicking the search button (on the Header Data subform), I wanted to use the text typed into the Header SN Field to search for the previous record in the Header Data table that has Header SN (field in Header Data table) = Header SN Field (field in form where user enters text). I could get this to run with no errors, but I kept getting the message saying that no matching record was found, even though there definitely is an existing record with the matching Header SN. My code for this is below.

Private Sub Search_SN_Button_Click()
If ([Header SN Placeholder] & vbNullString) = vbNullString Then Exit Sub
Dim strCriteria As String
Dim rs As DAO.Recordset

Set rs = Me.RecordsetClone  
  
strCriteria = "[Header SN]='" & Me.[Header SN Field] & "'"  
  
rs.FindFirst strCriteria  
  
If rs.NoMatch Then  
    MsgBox "Sorry, no such record '" & [Header SN Field] & "' was found.", _  
           vbOKOnly + vbInformation  
Else  
    Me.Bookmark = rs.Bookmark  
End If  
rs.Close  
txtGoTo = Null  

End Sub

After searching a bit, I thought the solution might be to have a text box and search button on the main form instead. The text box on the main form is called "HeaderSN". I am still getting the message that there is no existing record that matches. My code for this is below.
Private Sub Search_Header_SN_Record_Click()
If (HeaderSN & vbNullString) = vbNullString Then Exit Sub
Dim strCriteria As String
Dim rs As DAO.Recordset

Set rs = Me.[Header Data Form].Form.RecordsetClone  
  
strCriteria = "Header SN = '" & Me.HeaderSN & "'"  
  
rs.FindFirst strCriteria  
  
If rs.NoMatch Then  
    MsgBox "Sorry, no such record '" & [HeaderSN] & "' was found.", _  
           vbOKOnly + vbInformation  
Else  
    Me.[Header Data Form].Form.Bookmark = rs.Bookmark  
End If  
rs.Close  
txtGoTo = Null  

End Sub

Can someone please help me with this? I have tried a million different ways to do this and have been searching for days on different forums but I can't figure it out.