File Locked For Editing By 'User Name' On Save

i have this code to run autofilter in protected sheet2, assigned to a check Box,
but it gives me this Msg when i run the code by checking the check Box: File in use.
The file is locked for editing by the (my name). However, when i excute the code by F5 in the VBE window, it works fine also when i excute the code from Worksheet_Activate , it works fine

Sub t()
With Sheet2
. Protect "0", , , , userinterfaceonly:=True, Allowautofilter:=True
.AutoFilterMode = False
.Range("A5:DT5").AutoFilter
End With
End Sub