Only one Invoice is available and attached to all the activities

The stored copy of downloaded invoices are always written to the same file name and the uri stored in civicrm_file table is always the same (Invoice.pdf). This means the file is over-written each time an invoice is downloaded. And the attachment 'content' for the 'Downloaded Invoice' activity is always the last invoice downloaded.

To recreate:

• create a new contribution
• view contribution and click 'Print Invoice'
• view the invoice
• create another contribution for a different contact / different amount
• view contribution and click 'Print Invoice'
• now go back to the first contact, and view invoice attached to 'Downloaded Invoice' activity. It will be the invoice for the second contact.
  • • Original Post —
      When we create an invoice, its creating fine and associating with activity.

whenever we create new invoice its updating the existing invoice and associating it with the new activity but, only new file is available for all the activities as old one is over written with new one.