Excel Personal.xlsb saving document Macro - vba

Question

I have a macro to see if a cell contains this string if so executes a "save as" command with this set name standard. When I try to run the macro the if statements seem to not work. When I go through step by step it hits the if statements but saves the personal.xlsb instead of the file I'm working on. Here the code I know I have something wrong with it
Dim FName As String
Dim FPath As String
Dim answer As Integer
If ActiveWorkbook.Sheets("Sheet1").Range("A1") = "String1" Then
FPath = "C:\String1"
FName = Sheets("Sheet1").Range("A1").Text
If Len(FPath & "\" & FName) = 0 Then
answer = MsgBox("Do you want to Save File As: " & FName & "?", vbYesNo + vbQuestion, "Microsoft Excel")
If answer = vbYes Then
ThisWorkbook.SaveAs Filename:=FPath & "\" & FName
End If
Else
ThisWorkbook.Save
End If
End If
I am open to suggestion the most I was is to check if the file contains a string if so verify it does not already exist and if so just save instead of save as.

Answer 1

ThisWorkbook refers to the workbook where the code resides. Presumably, the code being in the Personal.xlsb, that is why it's saving the XLSB file and not the activeworkbook.
Try this instead:
Dim FName As String
Dim FPath As String
Dim fullName As String
Dim rng As Range
Dim s as String
s = "String1"
With ActiveWorkbook
Set rng = .Sheets("Sheet1").Range("A1")
If rng.Value = s Then
FPath = "C:\" & s
FName = rng.Text
fullName = FPath & "\" & FName
If Len(fullName) = 0 Then
If MsgBox("Do you want to Save File As: " & FName & "?", vbYesNo + vbQuestion, "Microsoft Excel") = vbYes Then
.SaveAs Filename:=fullName
End If
Else
.Save
End If
End If
End With