Open a Excel file selecting a option in Combobox

Hello

I need help guiding me with a Userfom i have .
I´d like to select a mouth in a combobox that opens a excel file after checking the file is not in use , what i have is this:

Private Sub ComboBox1_Change()
Select Case ComboBox1.Value
        Case "enero"
            Unload PLATINUM
            If IsFileOpen("I:\CONCIERGE\MarkuM M\BASE DE DATOS BITACORAS (NO TOCAR NO MOVER NI BORRAR)\BITACORA 2019 ENERO MARINA.xlsm") = True Then YAESTAABIERTO.Show
If Not IsFileOpen("I:\CONCIERGE\MarkuM M\BASE DE DATOS BITACORAS (NO TOCAR NO MOVER NI BORRAR)\BITACORA 2019 ENERO MARINA.xlsm") Then
Workbooks.Open "I:\CONCIERGE\MarkuM M\BASE DE DATOS BITACORAS (NO TOCAR NO MOVER NI BORRAR)\BITACORA 2019 ENERO MARINA.xlsm"
        Case "febrero"
            Unload PLATINUM
            If IsFileOpen("I:\CONCIERGE\MarkuM M\BASE DE DATOS BITACORAS (NO TOCAR NO MOVER NI BORRAR)\BITACORA 2019 FEBRERO MARINA.xlsm") = True Then YAESTAABIERTO.Show
If Not IsFileOpen("I:\CONCIERGE\MarkuM M\BASE DE DATOS BITACORAS (NO TOCAR NO MOVER NI BORRAR)\BITACORA 2019 FEBRERO MARINA.xlsm") Then
Workbooks.Open "I:\CONCIERGE\MarkuM M\BASE DE DATOS BITACORAS (NO TOCAR NO MOVER NI BORRAR)\BITACORA 2019 FEBRERO MARINA.xlsm"
            
        Case Else
    End Select
End Sub

but the code does nothing, it works only when i aply the code on a comand botton.
is there a different case using it with a combobox ?
thanks

thank you

it works fine now ...also thank you to trim my code since it will be usefull when file directory changes to modify quickly

sorry

i just find out that when the file is alrady open instad to show form YAESTAABIERTO.Show and close the workbook
excel still would opend it as a copy and does not show the YAESTAABIERTO.Show

it is working perfect moving the unload to the end of the code

thank you again