Corrupted fit file

6038.2025-08-01-16-09-25.fit

Hello guys, 
I have a big problem with this .fit file. 
I accidently deleted the acitivity instead of saving on my garmin edge 820. But luckilly I was able to recover it using Active@UNDELETE app. 
But when I'm trying to repair it with online tools - every one fails. The only output I was given is:

There were issues decoding this file

  • Invalid file CRC: Expected 0xE209, got 0x00. This may happen when something went wrong while downloading or copying the file.
  • Some Session messages are missing or invalid: Invalid messages are marked in red, missing messages are added and displayed in blue in the tables below.
  • The Activity message is invalid or a valid activity messages is missing: Invalid messages are marked in red, missing messages are added and displayed in blue in the tables below.
  • The file is corrupt: something went wrong downloading or copying the file?Hide errors
  • Position 8200: Invalid reserved 17
  • Position 16 426: Cannot add multiple messages of type file_id
  • Position 16 458: Cannot add multiple messages of type file_creator
  • Position 16 896: Invalid reserved 64



from this website:
https://www.fitfileviewer.com/


If you have any advice please help me.