Your Access database may have become corrupted and couldn't shut down properly, so the .laccdb file wasn't removed.  I suggest you create a blank database and import all the forms, tables, queries, etc., into it.

Access is now actually pretty good at cleaning up after itself.  I've had Access crashing occasionally and it rarely left behind a lock file.  So maybe your database ran into an especially nasty issue.

Thanks Kevin, I think I will use the backup file first . It seems ok , if not , will follow your instruction