run time error 13 Type mismatch

[GEORGE PERRY]

Please i need help. my Excel VBA Application is giving this message

run time error 13 Type mismatch

Sub show_inventory()

Dim sh As Workbook
Set sh = ThisWorkbook.Sheets("Inventory")

sh Cells.Clear
ThisWorkbook.Sheets("Product_master").Range("B:B").Copy sh.Range("A1")
sh.Range("B1").Value = "Purchase"
sh.Range("C1").Value = "Sale"
sh.Range("D1").Value = "Available Stock"
sh.Range("E1").Value = "Stock Value"

Dim lr As Long
lr = Application.WorksheetFunction(sh.Range("A:A"))

If lr > 1 Then
sh.Range("B2").Value = "=SUMIFS(SALE_PURCHASE!D:D,SALE_PURCHASE!B:B,INVENTORY!A2,SALE_PURCHASE!C:C,""PURCHASE"")"
sh.Range("C2").Value = "=SUMIFS(SALE_PURCHASE!D:D,SALE_PURCHASE!B:B,INVENTORY!A2,SALE_PURCHASE!C:C,""SALE"")"
sh.Range("D2").Value = "B2-C2"
sh.Range("E2").Value = "=VLOOKUP(A2,PRODUCT_MASTER!B:C,2,0)*D2"

If lr > 2 Then
sh.Range("B2:E" & lr).FillDown

sh.Calculate
End If

sh.UsedRange.Copy
sh.UsedRange.PasteSpecial xlPasteValues

Dim inv_Display As Worksheet
Set inv_Display = ThisWorkbook.Sheets("Inventory_Display")
inv_Display.Cells.Clear

If Me.Txt_Search.Value <> "" Then
    sh.UsedRange.AutoFilter 1, "*" & Me.Txt_Search.Value & "*"
End If

sh.UsedRange.Copy inv_Display.Range("A1")